Picture one shows the first step done. No sanding yet. Picture one is after the first pass at sanding to the finished shape. It is not easy to see from the picture but there are easily visible slight low spots. Per the instructions you just go back and add some glass and fill them in. Not hard at all.
Picture three is after all the low spots appear to be filled. You then give it a good shiny coat of epoxy without and glass. You sand that down to a nice even finish and there should be no low spots remaining.
