The trick I use for doing freehand sharpening is to color the bevel with a sharpie, that will show you if your angle is correct. You don't need a lot of stones,

The trick I use for doing freehand sharpening is to color the bevel with a sharpie, that will show you if your angle is correct. You don't need a lot of stones, I just have one Sharpal double sided diamond stone, and then I move to a leather strop with 1 micron diamond emulsion compound. Another very useful thing is an inexpensive jeweler's loupe so you can actually diagnose issues like not having removed the burr.