An increasing number of departments are requiring college, usually 60 hrs or an Associate's degree. Unfortunately, when you first become a cop, it is not always with the dept of your choice - you submit a lot of applications, and hopefully one will accept you! So, it is a good idea to have college. Not only will it help you in the hiring process, but many depts pay extra for education, and, it will help you to advance through the certification levels, which, they also pay extra for!
It is easier to go to school while you are still young. The older you get, the harder it is! It's also easier to go fulltime before entering the workforce, than doing it parttime while working fulltime. However, if you want to go for a bachelors, you might wait until you are working. Why? Some depts have tuition assistance! If you can get someone else to pay for part of your education, that's a pretty good deal!
I don't know if you have considered the military, but I know a lot of depts have many officers with military background.
I wish you the best - let me know if you have more questions!