Help me level up my Mastery Champions

Ok so I really like to use champions that people barely play sometimes. Well my 3 champions I really wanna master is

http://na.leagueoflegends.com/sites/default/files/styles/scale_xlarge/public/upload/pd-banner.jpg?itok=gp5ZYijN

http://na.leagueoflegends.com/sites/default/files/styles/scale_xlarge/public/upload/arcligh_velkoz_splash_1920.jpg?itok=ctostKLA

http://www.mobafire.com/images/champion/skins/landscape/katarina-mercenary.jpg

Katarina

Draven

Vel'koz

Katarina is already a m4 draven is m3 or soon to be m2, and vel koz is m2 since draft and blind take a long time to finish I wanna know if there are different types of game modes that can level up my champions. My goal is to make Katarina m5 draven m5 vel'koz m5. So are there any tips and tricks to getting more points for your champions in draft or ranked or blind (I can be able to play ranked) that can give me a lot of points? I just played ranked only 1 so yeah. But if there are any game types that can give me more points plz let me know I don't want to stay in the computer 2 or 1 hour in the computer for one game and it won't give me xp that much. If you are going to say (creep score aka cp) idk what that is but if u can tell me thanks