In Dorico, 0pen the pulldown menu for “Library” and choose “Instruments”.
Then filter by family and see if any of the instruments you want to use are already there (e.g.: hand clap). Then create your own instrument/s following the instructions on Dorico Pro Help (https://www.steinberg.help/r/dorico-pro/5.1/en/dorico/topics/library/library_instruments_custom_creating_t.html) - creating custom instruments.
Once created, go to set up and create a player that will play your instrument/s. Then assign them your instruments. After this right click on the title of the player to pulldown a menu and choose “combine instruments into kit”.
Steinberg
Then go into kit and just vertically position your instruments in the order wanted/needed.
Here’s a sample I created
Here’s the Dorico file for you to look at:
Percussion Kit Sample.dorico (457.4 KB)
Hope this helps.