Giving Up Soda

What's is the best way to slowly give up soda? Sadly I am addicted and I'd really like to give it up. When I was younger my parent's stopped buying soda and I was forced to give it up cold turkey. I could have it every now and again but didn't get addicted until about a year ago. I REALLY want to stop but not cold turkey because I get bad caffeine headaches and with everything going on it's the last thing I need right now.

Any suggestions? How did YOU do it?