So, I have no problems getting to the Mun from a Kerbin parking orbit. I can land pretty easily. The problem is, I use a LOT of fuel on the descent path because I end up freaking out and trying to cancel out some of the orbital velocity way sooner than I probably should, which basically leads to me fighting physics when I could be using the high velocity to my advantage to speed the landing process up. Theoretically, I know this. When I see the Mun below me and my distance toward it decreasing, I start trying to fight it anyway. This leads to me having very little fuel to establish a Munar orbit that's efficient, and leads to me having to find creative ways to make it back to Kerbin with little fuel after I reach a stable low Munar orbit.
Basically, at what point do you start bleeding off some of the orbital velocity during your descents?