Ok I recently bought the game, and I’m an absolute noob.
I fill my super bar and check the command list for my characters super move, but I can never manage to pull them off! Take Seth, for example, I use his Tanden Storm super move and it charges a mini black hole for about a second then he gives in. I can barely do Ryu’s Hadoken (The super move one, not the normal Hadoken, I just forgot the full name). The button combo’s in the list are very vague and confusing - I need step by step information and don’t leave anything out please. 
Which punch or kick button you use will normally make a different version of the super come out, keep that in mind (e.g. Seth’s hp tandem storm sucks in from full screen, though takes a lot longer to startup). Also try entering the motion as :d::df::qcf::p: that’s all you need and it’s easier for many than :qcf::qcf::p:. And practice it in training mode with input display turned on.
Edit: also if you get hit when the move is starting up it won’t come out.
For the Seth one, you are getting it right, you just aren’t hitting your opponent. Most supers have the same motions. For almost all motion based characters (like Ryu or Seth), it’s a double quarter circle forward, then a punch, or kick. For some, it’s double quarter circle back, but the motions stay quite similar, so you don’t have to change around a lot for every character, unless you’re going motion to charge, but that’s a whole nother story my friend.
