A trip down memory lane here........simple really.
We use to take a roll of toilet paper (whole) and soak it in kerosene, place this in an old tobaco tin (screw lid type, havent seen in years) punch some holes in the top with a nail (about 15-20 small....like 1/8"), then light the tp with a match and seal the lid.
It would burn for about an hour give or take depending on the holes. The tobaco can gets real hot on top but stays pertty cool on the bottom.
There are a few risks in using this home made heater that should seem obvious but the thing to remember is there is noway to put it out quickly and noway to regulate the heat.
ps. have fun fishing and please put a few back for the next guy