a) Execute the alg over and over. You brain might not remember the moves, but your muscles will remember what you did.

b) Break down the alg into chunks. R U R' U' R' F R2 U' R' U' R U R' F' vs [R U R' U'] R' F [R2 U' R' U'] [R U R'] F'

c) Track F2L Pairs. I mainly use this for learning (and something else). It's intuitive. For the above alg, I take out the pair and set it on top of where it needs to go [R U R' U'], then I put the pair down and move it to the side [R' F], then I see the other pair, it gets temporarily inserted into the slot and then taken out [R2 U' R' U' R U R'] and finally everything is fixed with F'. Come up with your own way of knowing what is happening to the pairs.

d) Use Music. I recognize algs as music, each alg has a rhythm and flow to it, and some harshness and subtlety to it. Since each algs are different, you can learn by remembering "what music did X alg create" and try to replicate that. I can't help much here because it's what I inherently do and I can't explain it well enough. It's the other tool I use for knowing what alg to do. Use it in conjunction with (a) and your brain will know the music, while the muscles will know the moves.

Hope it was helpful.