How should I plan my 4 yrs in college to become a good computer science engineer?

Few things you should do while your 4 years of engineering.

1. Keep your database of knowledge well equipped with the basics of each and every subject possible.
2. Get few certificates for yourself by doing few certification courses like ethical hacking, OCPJP, etc. Remember this is important as not many are doing it. Don’t select any one certification course instead go for everything you can study. And i recommend you do these certification courses before your third year.
3. In third year during vacations try getting any good internship where you get some practical knowledge about your field.
4. Keep your final year free for placements or/and to crack any competitive entrance exam you like. If you are sure from earlier years of engineering that you are going for some PG courses then start studying for the respective entrance exam(like CAT,GMAT,GATE,GRE) simultaneously with your engineering. Reading a novel to increase your reading skills, solving quants sometimes(this may also help in clearing aptitude tests of various companies) will help you alot while preparing for these exams.