Yes dazzle painting can be a problem. For the straight lines mask with THIN masking tape, I use Tamiya or Magic tape, and for the curved line I use frisket , an artists masking paper. As a precaution against paint bleed I always over paint with the base colour and then paint the colour I want. Thats rather badly put but if the base colour is white i repaint the white and then whatever the camo colour is.
Dai.