University of Illinois Chicago transfer into U of C

Hello! I have a few quick questions. I’m planning on attending CC for about a year and then transfer into UIC to complete Freshman and sophomore year in Computer Science. After this, I’m going to try to transfer into either U of C or UIUC. I know those are really tough schools to transfer into. Especially if I want to get into the CS programs there. But I am determined to work really hard since U of C was my dream school. It’s just too bad that my skills for ACT and SAT were not so good. I had a great HS GPA with a 3.8. But the standardized tests really killed me. No matter how much I tried, I still ended up in the low 20s. Highest was a 23. But anyways, for those who were able to transfer to U of C from UIC, what did you do to make it to that level? What type extra curricular activities should I complete? Tips from other students would be appreciated too. Thanks!!

(NOTE: I posted this same post on the UIC forum as well. But I wanted to your tips on what to do)