So, I have been looking into voice character acting like the voices you hear on cartoons. It is amazing stuff!!!
I have found that a lot of it is practice as one would imagine. However a lot of it has to do with creativity as well. When creating a new voice for a character it is important to think about the motives, attitude, and overall personality. Some tricks in creating a voice are changing pitch, speed of speach, and dialects.
If you are interested in more about character voices be sure to check out Billy West the name may not be familiar but I'm sure his voice is. Billy has done voices for Futurama, Ren and Stimpy, Doug, as well as countless other cartoons.
My personal favorite though is Mel Blanc. If you don't know him he created all the voices for Warner Bros. cartoons. Mel has tons of range as far as different characters. I feel as though many people do lots of voices but usually I can hear similarities in all of their characters. Mel on the other hand is so good it is almost impossible. He is a one man show literally jumping from Bugs to Daffy to Elmer and back to Daffy it is amazing that he can even keep all the voices organized in his head.
well keep practicing those voices