A candle is a fantastic lighter of anything and doesn't waste lighter fuel and has many other uses.

Several layers of aluminum foil shaped into a C-shaped windscreen works very well and has many other uses.

I've found that a cup or pot lid is essential, because in my experience, even trying to use an aluminum foil cover sort of funnels the fumes from the burning Esbit fuel into the food/water you're heating tainting it badly.

Finally, the Esbit cube lights much easier if you light a corner first. In fact, you can chip off a corner, light that, and then use that to light the bigger cube with ease.