Hey Olive, by left to right you mean your character is facing right?
I find, as a new player, the execution barrier can be frustrating at times, especially because no one online can/will articulate the procedure. I will try to articulate as best as I can.
I’m going to assume you’re using an ball top arcade stick. Since you’re doing a cancel into double qcf right, the motion has to be fairly fast, so I don’t recommend you to go back to neutral (or pausing) after doing the first qcf. Try using the input shortcut to do one fluid 450 motion: down, down-forward, forward, up-forward, up, up-back, back, down-back, down, down-forward, forward. Or, you can do: down, down-forward, forward, (omit the up-forward to up-back and pull straight from forward to back) back, down-back, down, down-forward, forward.
Make sure you hit the corners. When I hold the stick, my index finger is at the near apex of the ball top. If the very top is 12’o clock, my index finger would be at 11 or 10’o clock. When I do double qcf to the right I, go from neutral to down, and push the ball top to the right with my index and middle finger until I feel I hit the corner. Then, bring the stick upward to the right. I tried Daigo’s hold initially, it didn’t work out for my character (Makoto). According to Daigo, that hold is more suited for SF4 (he used the wine glass hold for 3S if I remember correctly).
Here’s a vid on top 3S player’s hands, pick your favorite:
My hold is similar to Mimora’s (goto: vid’s description), except I don’t use my ring finger to do any pushing (because it fucking hurts).
If you’re are doing a link or a hit confirm, you’ll have extra time. Use this time to do the first qcf, let go and go to neutral and do the second qcf. As someone who is starting out, make sure to do (push) the qcf’s forcefully so you’ll hit the corners.
Remember to not be anxious and do one fast, sloppy polygon motion. If you’re not getting it, aim to just have the super come out after the normal (it doesn’t have to be a combo–you can do the normal, pause, then super), then you can proceed to speed up. It’s a tedious process–I still need to go and practice every so often (especially if I don’t touch the game for a while)–so don’t get discouraged, because you’re playing a man’s game.
Edit: If you’re practicing w/ Chun, try doing down mk first, pause, do the super starting from down. Make sure you’re executing the super correctly from down before comboing the whole thing together. Essentially that’s what cr.mk xx SAII is; you’re just integrating 2 separate moves into one motion.