In the cold north I prefer an oil stone since water whetstones can freeze and break down. I add oil until the stone stops absorbing it and it stays on top. I also #3dprint an angle quide to help know which angle you need to hold the knife. I don't have a picture of mine but very similar to this screen shot of one. I count the strokes I do on one side and then do the same on the other. I also let the weight of the knife drag across the top of my fingernail like I'm trying to cut through it but not applying pressure. If dull there is no resistance or if large burr there is no resistance and if sharp it catches my thumb nail and causes resistance. Flicking your thumb pad against the edge can sometimes give a false sharp if the burr is really large. The knife may catch your skin but won't cut paper well. This is all just my opinion. Thanks for starting the conversation. #edc #sharpening #whetstone 
Discussion
Nice angle guide!
And yes, letting the knife fall on the nail is a perfect quick sharpness test, if it wiggles it ain't sharp enough.