okay you'll have to spend SOME money but here's my solution;
find your local garden shop and buy some cheap, premix soil. don't get anything with nutrient bases pre mixed or it will kill your plants. just some good old fashion soil. you don't need a lot.
the reason you shouldn't use soil from just outside is insects and parasites. which will kill them.
next is some solo cups, fill the solo cups with your fresh soil.
get a spritzing bottle, like the kind for spraying your cat when he's being a dick.
you'll also need a large plastic bin, preferably one that is clear with a top on it.
okay now what you do is keep your clones in the little cups in the bin. spritz it a couple times a day. set it out in the sun when you have time to but make sure you bring it in at night. DONT completely seal the bin. it will suffocate your plants.
the best method would be punching some holes at the top and bottom like pic related to get some airflow going.
if everything goes as planned, and they stay moist and humid and warm they should last you for about a month.
DONT over water them. if water collects in the bottom of the bin make sure you dump it out as IT WILL MOLD.
$10 potting mix
$4 solo cups
$10-15 plastic bin
$5 spray bottle
use some cheap nails and a torch lighter to get nice even holes in your bin. if you don't put holes in your bin, your plants will most likely wilt