I’ve never been much of a fighting game fan but, now that Killer Instinct is coming out i’m really interested. I’m using umvc3 to practice, but I wanted to know if you guys (as fighting gamers) have any tips on how to become better?

first off im not sure how play UMVC3 go hand in hand with killer instinct. if your not into fighting games, i suggest you start of by playing SSF4. It generally welcomes new and old players to genre. and just practice to be honest thats all i can say. hope this helps

Yes SSF4 would be a better preference to start off for fighting games. Especially with KI, it is more similar than that of UMVC3.
Practice and practice. Look up guides, videos and such. Learn the basics, then go advanced.