I really love looking at fighting matches and the games in general are very interesting to me, but I suck ass at them. Anyone knows any tips to start properly practicing? Street Fighter Alpha 3, MK9, and the first Darkstalkers are the only fighting games I actually put some time into a long while ago
The question is somewhat broad, and I think the answer changes slightly, depending on the game and your experience level. These tips were thought up under the assumption that you will be playing against others online, but they may be somewhat applicable for single player as well to a degree.
If you want to improve in playing the genre as a whole, I'd recommend practicing execution of special moves, especially if you wish to play the older titles. Practice common inputs until they're second nature to you on both sides of the screen. Knowing a character's good buttons to use and a basic combo or two can often go a long way.
There are usually character guides on YouTube or on forums/wikis like the
Supercombo Wiki (mostly for Capcom games, but also has others),
Mizuumi Wiki (for lots of niche games, as well as some good Darkstalkers pages), or
Dustloop Wiki (for Arcsys games) which can help set you on the right path. Older games may have character guides on GameFAQs and the like.
If you are unsure on how to use training mode in games - I really like using training mode to practice common scenarios that happen in a match. Brian_F has a great video (around 20 minutes long) on how to use training mode in SF6, which is posted below. Although most games will not have training modes as feature-rich as SF6's, the basic concepts he showcases still apply to most games.
But most importantly of all, make sure that you aren't forcing yourself through the learning process if you aren't having fun. It's totally alright to be figuring things out at your own pace. This genre can be difficult sometimes, but it is incredibly rewarding.
I kept these tips mostly general, but keep in mind that system mechanics (parry in SF3, advancing guard in MvC/Darkstalkers, drive system in SF6, etc.) are game-specific and are also very important to learn and incorporate into your gameplay.
...sorry this post is rather long winded. Hope it is helpful to someone in some way!