Instead of modifying commands, why don't you do it the proper way.
Go into your XGUI and remove access to that command from all the groups and then add it to just yourself.
Make sure you don't deny access as deny supersedes allow.
Example: ( you want to make slay for you only )
in XGUI, uncheck slay as a command that admin/superadmin can perform.
in your server console type : ulx userallow reese "ulx slay"
If you're creating your own commands, you can just leave out the line that sets the default access and it'll default to none. (meaning noone can run it until you give permissions manually)
