1) Press [STORE]

2) Choose to store as a new performance
3) Give your Performance a meaningful and unique name

Quick video at time where this is shown:
https://youtu.be/WIumqa4bEZA?t=88

Every [STORE] operation places your current working changes into the User bank with a Performance name you assign. Subsequence [STORE] operations will give you the choice to overwrite your current Performance of the same name or save the Performance as a new name in order to preserve the original.

The User bank is memory inside your Montage. There is no need, therefore, to have a USB drive attached.

Brand new to the Montage. In the process of figuring everything out. Saving favorite sounds to User 1, easy. Working on layering sounds. Here's my question. Once I create a "layered" sound I like, how can I save it, and to where?

You’ll want to get used to the MONTAGE terminology.

STORE is the operation that writes your edited Performance data to the internal USER Bank. There are 640 User Bank Performance locations. You can view and manage what is currently in your User Bank, by pressing [UTILITY] > touching “Contents” > “Data Utility” > touch the Folder named “Performances”. It will inform you how many out of the 640 you have occupied. The STORE operation is always one Performance at a time. Data stored to the internal memory will remain between power cycles… Data in the User Bank should be “Saved” to a USER File before you Load a new USER File. Loading a User File replaces the previous User File.
It is the internal Stored data that is Saved to a File.

A USB stick 4GB, 8GB, 16GB are typically used

SAVE is the operation of writing a file to an external storage device (a USB stick, a computer or laptop, a tablet or iPhone, or to the Cloud (via the app: Soundmondo). SAVING data to a USER File (.X7U) will document all the User and System settings for the synthesizer tone generator. Performances, Arpeggios, Motion Sequences, Live Sets, Waveforms. The USER Bank is where you assemble your customized data which you can, if you wish, install to semi-permanent/rewritable FLASH ROM (you do so by saving as a Library File .X7L, then installing that File in a separate Load operation)
A backup File .X7A will Save all MONTAGE data, including installed Libraries, Songs and Patterns. This is useful if ever you need to rent a MONTAGE — Loading your BACKUP File will turn the rental instrument into “your instrument”.
The computer utility MONTAGE CONNECT allows you to make individual Performance files using the ability to BULK DUMP the Performance settings via USB-MIDI. You can either file them yourself on your computer or you can transfer them to the Cubase Media Bay. The iOS app, Soundmondo, allows you to similarly save individual Performances by bulk dumping the data via USB-MIDI.

Thanks for this info. So I pressed Store, then when I press "Performance" I can then scroll through all my saved layered sounds using the scroll wheel. Is this correct?

Then.....how do I DELETE one of these saved "performances" if I no longer need it, and don't want it to take up space? I hit "Edit" but didn't find any function that allows me to "Delete" the saved performance.

Instructions allowing deleting multiple at a time (if you wish):

Source: https://www.yamahasynth.com/ask-a-question/how-to-delete-a-performance-in-montage

Press [UTILITY] > select "Contents" > "Data Utility" > select the PERFORMANCE folder.
This will display all of the current Performances in memory. The User memory can hold 640. Your Motif XF will only fill 544 of the 640. (512 normal, 32 drum).
You can view them by Name or Date.
Touch "Job" in the upper right corner, you can now SELECT (places a check mark in the Performance box) the ones you would like to Delete.
You are shown 12 Performances at a time. You can scroll Pages at the bottom of the screen.

another response to this question ...

Source: https://www.yamahasynth.com/ask-a-question/deleting-performance-from-user-bank

press 'HOME' - 'UTILITY' - then tap 'Data Utility' on screen and select the 'Performance' box from those that appear. This produce a listing of all User Pfs on Momtage, 12 to a page. On the bottom you'll see a 'Name' box - tap that and the Pfs are listed alphabetically (easier to find) and at the top right you will see a box labelled 'Job' - tap that (it lights up green) and you can then tap all the Pfs you wish to delete (they light up with a blue arrow) and a box at the bottom says 'Delete' - once you have selected the ones you want to delete, tap the 'Delete' button and they will be deleted.

A video:

https://www.youtube.com/watch?v=5O9covEh8vg

Note that each of these were the 1st three search returns from a google search:

yamaha montage delete performance

Thanks for this info. So I pressed Store, then when I press "Performance" I can then scroll through all my saved layered sounds using the scroll wheel. Is this correct?

Then.....how do I DELETE one of these saved "performances" if I no longer need it, and don't want it to take up space? I hit "Edit" but didn't find any function that allows me to "Delete" the saved performance.

Answered in my post above:

STORE is the operation that writes your edited Performance data to the internal USER Bank. There are 640 User Bank Performance locations. You can view and manage what is currently in your User Bank, by pressing [UTILITY] > touching “Contents” > “Data Utility” > touch the Folder named “Performances”.

Thanks. This is all VERY HELPFUL. Hope you don't mind another question. I'm now able to save my own created layered sounds as "Performances" and am also able to delete them according to the instructions above. Fantastic!!

Now, when I power the machine down, and then turn it on a day or two later and want to recall those saved "User Created Performances", how can I get directly to them (User Bank)? When I press the Performance key, it simply lists all the individual "Stock" Montage sounds to scroll through. How do I get to my saved layered sounds quickly? The User Bank?

From any [PERFORMANCE (HOME)] screen:
Press [CATEGORY SEARCH]
Set the “Bank/Favorite” option = USER
You do so by either tapping that box to see a list of Banks, or by pressing the [PERFORMANCE (HOME)] repeatedly to toggle through the Banks.
Your User Bank Performances will now populate the “Performance Category Search” screen.

I get to my user sounds quickly by placing them in [LIVE SET]. There's a configuration option to default power-on to the Live Set. This is my configuration. Now I have 16 User Performances sitting in front of me ready to select any of them right away and simple paging through for more.

Although sometimes I filter [CATEGORY SEARCH] by the user bank - more typically I will press on the magnifying glass in the upper-right of [CATEGORY SEARCH] and type in a partial search of letters in my User Performance. This is why naming your User Performances can be important. The names you choose. If you name all of your own Performances "STV ????" (???? is whatever else you add) - then all of your own work can be found by searching for "????" no matter if it ends up in a Library or User bank. Filtering by bank is faster for this kind of thing. I don't actually do this myself. I'll name by song then search for some unique string in the song. How you organize is wide open. There's other ways of managing this too. Favorites, Category (of your Part 1), etc.

BTW: adding Performances to [LIVE SET] is relatively simple.

https://www.yamahasynth.com/learn/montage/mastering-montage-performance-basics-and-live-set-1

See the last paragraph. There's a 2nd part to this which is linked in the article which goes over more Live Set details.

You may wish to keep your Live Sets for their intended purpose… a “play order” listing for when you need to recall Performances in a specific order (like when on stage). It largely depends on the number of Performances you’re dealing with.

The “Performance Category Search” allows you to zero in on your data both quickly and efficiently. Potentially there can be 640 User Performances that you might accumulate. Hunting through the Live Set screens will get old rather quickly as soon as you have more than a PAGE or two… imagine having 40 screens of 16 slots!

The “Bank/Favorite” option found in the SEARCH engine will let you get to your data by Bank. The “Attribute” lets you further refine the search. The “Main” and “Sub Category” refine this even further.

When STORING your own User Bank data, the Main and Sub Category of Part 1 define where your Performance is catalogued by the system
Looking for the Lead Trumpet sound you customized? Your *search* would be:
Bank = User
Main = Brass
Sub = Solo

Sometimes you want to just use a factory sound: marking sounds you use again and again as “Favorite” is extremely useful.
A yellow star will be placed in the Performance Name box. By tapping [CATEGORY SEARCH] twice, all your Favorites will appear in the results field, whether Factory Preset, User or Library.

Quickly, using “Main” and “Sub”, you can be looking at all your Favorite Brass Solo sounds, in just a few taps.
There are several ways to Set as Favorite:
__ you'll see “Set” on the search result screen
__ tap the Performance Name box on the HOME screen to see the pop-in menu, tap “Favorite”

You should ALWAYS rename your own Performance data (or at least mark your version with a yellow star) otherwise you will need to go through extra steps to find your version versus the one you started with. When you press [STORE] you are offered a chance to Rename your data — take it!