Guile is a good matchup for Vega. You have a lot of options to get through his fireball game, and once that’s dealt with, he’s a fairly simple and one-dimensional character.

Usually the match goes like this: Guile tries to establish his sonic booms, you jump them and slowly push him into the corner and eat him alive with long range pokes.

When Guile throws a boom, you can A) Slide at him which often trades, B) C.MP early to hit him out of it, or C) jump in. He recovers fast enough to block your jump in, but not fast enough to get out his C.HP antiair, so just do a blockstring and push him back.

Once you have him in the corner, stand outside his C.MK range and fish for opportunities. C.MP, Slide, Jab Roll are all good. Sometimes you can predict a sonic boom and get a J.MP, C.MP combo. Mix in a lot of neutral jumps at this range, where his Flash Kick will miss and you can punish him. Once in a while sneak in a throw after a Jab Roll or poke. In general, he’ll take more damage from your pokes than you will from blocking sonic booms.

The only thing time you should be worried is with the top level Guile players, who are extremely basic and precise. They don’t throw bad sonic booms which are unsafe, and will reliably Flash Kick all your attacks. Top Guiles can also play aggressively well, and throw Jab Sonic Booms into throw mixups. You have to match by tightening down your game as well. Throw in fast normals like S.LK to bait out Flash Kicks. Don’t jump in anticipation of anything since Guile will always have antiair ready. Establish purposely weak strings like Jab Roll, C.LP, Jab Roll. Let him interrupt this with a Flash Kick once or twice, then stop the 2nd Jab Roll and he’ll often still react to it.

The main problem with the match is Guile throwing a slow sonic boom at mid screen, then walking behind it. If you hit a normal you’ll get hit, if you jump he’ll walk under you and throw, and if you just block he’ll go for a throw. This is a bad mixup for Vega, so avoid this range. Instead stick to sweep range where you can pressure with pokes and interrupt booms and normals. Or from max range, do wall dive fakes to see if you can bait a whiffed normal or a late sonic boom. Stay extremely cautious since he can walk 2 steps forward and be in range to catch your fake dives with a J.HK.

Guile’s anti-airs are extremely effective against wall dives. His J.HP and J.HK both have long horizontal range and stuff you well. The J.HK reaches so far that you shouldn’t be doing wall dive fakes unless you’re at max possible distance. C.MP doesn’t look like good antiair, but it catches dive claws very well. If you see this choice a lot, steer farther away on descent and aim your claw for the end of his limb. C.HP has great reach directly over his head, but if you predict it’s coming, you can steer around it and catch him in a grab. You especially don’t want to get stuck in the corner against Guile, because then your wall dive can be crushed with an easy jump back J.HP. If you need to get out, the safest choice is C.LP cancelled into a wall dive off the opposite side of the screen. Even this can be Flash Kicked, but Guile usually isn’t looking for this unless you overuse escapes.

Guile’s neutral normals have good priority and good range, but they’re slow to come out and slow to recover. Sobat Kick and C.MK are two prime examples. Use quick C.MP pokes to either interrupt his normals or whiff punish them.