A few months ago I had been disappointed with the finish on some of my models. I felt, specifically, that this was due to issues I was having with paint consistency. My Vallejo paints just seemed too thick and using water just wasn't working. As a result I felt my vehicles had very rough looking surfaces and my infantry figures looked very 'heavy'.
I had just been using water to thin my Vallejo acrylics and it just didn't seem to work. The paint either ended up far to runny/wash like or it just didn't seem to coat the model properly. I had a few people offer suggestions and did a bit of hunting about on my own.
The original discussion can be found here.
Eventually I settled on this: