Learn proper speeds and feeds, don't use cheap tooling. Cheap tooling doesn't cut very well and is going to make for a lot of deburring and hand finishing for you to clean up. We use high performance end mills, inserts, etc and carbide for everything except some drill bits. But that isn't practical for someone like you just doing it on the side. We have probably almost as much money in tooling as we do in actual CNC cost.