Daily Habits to Prepare for Graduate School

To prepare yourself and keep your skills in shape, one idea is to gradually go through advanced undergrad/beginning graduate textbooks, including doing exercises. (Reading is good, but also doing exercises (both theoretical and programming) is better.) It might also be good to do a programming project or two, from which ideas might naturally stem out of your reading. What to go through also depends on your situation (what area of CS, what you learned already, whether you're already programming for work...)

However, to make yourself a good candidate for graduate studies, you'll also want good letters of recommendation, which means you want someone (ideally an academic) familiar with your further preparations. Therefore you might try contacting one of your old professors or a professor geographically close to you to see if they're willing to help give you some guidance in your studies and/or involve you in a research project.

See also: How to show graduate schools my strong self study background?