First, you must have a group called Respected in ULib. Various ways to add that, easiest being gmod/settings/users.txt, second being ULX, third easiest (and really, only if not ULX) being editing the groups.txt file in data/ULib.
Once done with that, you should be able to use the gui menu to edit your respected allowed tools following directions from the Urestrict thread. For default, have to edit your default txt config file that comes with URestrict for the default loadout.