How can I make a weed killer for my lawn? I hate having to hand pull

Dandelions are the first food for the bees. Leave them at least until the rest of the flowers bloom. If you really need to kill them and don't want to use poison, e.g. Roundup try vinegar and epsom salts. Make a solution of 1 gal water 1 cup (or more) vinegar and one cup of epsom salts. Mix thoroughly. This kills by making the soil very acid. It also allows for too much magnesium to be taken up by the plant. Be careful with it though, anything that likes neutral ph will not grow there for awhile until you sweeten the soil. The other thing you can do it not mow your lawn closely. Let the grass grow to about 5" before mowing. Keep it mowed high, that will help crowd out the dandelions.

Pouring boiling water will kill them and not ruin the soil, but you still should pull them out.