Don't laminate them. It can make them stiffer & harder to fold and also more bulky. At night glossy laminates reflect light making parts of the chart hard to see without moving the chart around. You're limited to using a 'special' marker on the chart ie you can't use just about anything that comes to hand, and with some markers you then need to carry a solvent to remove the ink.
Leave the charts as plain paper and use a soft pencil. I use a 2B, nothing harder so no HB or H series. A 2B is soft enough to write on the chart and be erased easily with a rubber/eraser whilst still hard enough to avoid wearing down too quickly. An added bonus is that it will write on whiz wheels & flight plans/PLOGs too so you don't have to carry additional, specialised writing tools. 2B is nearly always available as the 'soft' option for mechanical pencils too.