The simplest brisket rub is just salt and pepper. But lots of people use more than that, even if they say they don’t.You could easily just grab a rub off the shelf or get some basic ingredients and make your own. Before you apply the rub, you’ll need to decide if you want to slather it with a binder. Some people don’t use a binder, some use mustard, mayo, or anything else that will get it tacky so the rub will stick. Lately I’ve been using a mix of yellow mustard, worcester sauce, and sriracha.