I’m like you when SF4 came out. Been out of the fighting game stuff since the late 90’s with Super Turbo. I didn’t play a whole lot of Versus series or Tekken and other SF imitators.
First thing’s first when I picked up SF4 was hit up training mode. I picked Cammy and then Bison. Bison has this universal crouching short, short, short link that’s pretty much the bread and butter combo for 98% Bison players. It took me a long time, but it didn’t help that my TV has a little lag. So my timing was off for like months without me realizing it.
Do the challenges, learn all of the moves and their commands. Get accustomed to repeating the special moves on pad or stick. Get those timings down. This is where the muscle memory and reaction helps.
Play around with the normals, see how they hit at which distances the most and what not. This would help some of your footsies and anti-airs. Think about these when you’re practicing online or offline. I just picked up Dee Jay and Rose this month. I’m not doing toooo bad with them. Practice the combos and memorize the timing for the combos that hit. There’s some blockstrings that have uninterruptable portions, and some that do have it if you mistime and the other person blocks. This game has very lenient input windows so you will run into heavy uppercut or command grabbing mashers. It will be easy for them to cut through your missed link combos and whatnot with these invincible-at-the-beginning moves, so don’t feel too discouraged if it happens to you. It could be lag on your tv, your internet, or simply you were just a little mistimed. It’s okay, practice more later on.
I just try to remember like 3-4 combos per character (Rose doesn’t have thaaaaat many to remember so I’m good) and just practice those in training mode about 1-2 hrs every session before I hit up ranked matches for quick and easy learning. I pick ranked and I create the lobbies so I don’t have to wait too long because whoever has a green connection to me will naturally just try to join me first. I have like 3.2k BP with Dee Jay so far and it’s been an uphill battle. I started off with the basic c.LP c.LP c.MK sweep combo on people for like half the time and I’m moving a bit toward some block string combos and eventually I will learn and adapt a few more higher damage punishes.
The next step, I’d recommend get acquainted with your characters match ups. Online is not as bad as people make it; there is certainly a limitation due to a lot more popularity with some characters online but it’s still a great training ground. Learn and see how people beat you or you beat them. You landing some damage? How? He or she is hitting you? How? Think about some of these things and see if you can pick out a way to counteract it. *Okay, so this guy pile drivers/ typhoons me every time after I hit him with X or Y and I’m trying to block the next hit, let me hit him with X or Y and then JUMP immediately and see if he whiffs his throw and then punish. *More times than not, this works a lot against scrub grapplers a few times a round. It may stop working after 2-3 times but you get the point.
Practice, practice, practice.