i love making home made mustard it a nice hobby but if you make the good stuff it can get expensive.
the are lots of videos that tell you how.
there are so many diffrent kinds you can make.
if you just stating out i recommend you start with yellow mustard as it the most common and cheapest youll find to experiment with.
also one thing few people mention in tutorials is that the colder the liquid you use the hotter the mustard will be.
the longer you leave it canned the better aswell