Place Jiffy starters already planted with seed in a sunny window - most plants need sunlight to germinate/ sprout.
Try to place the starters in the sunniest window, generally southern exposure, although any bright window will do.
If seeds were started indoors, gradually introduce to full sunlight (notice gradually) so that plants make a gradual adjustment to full sunlight (hardening off/ prevents sunburn)
When you place the started plugs into the warm soil, I always cut the nylon netting of the Jiffy starters with sissors
to encourage the roots to spread outside the bounds of the nylon netting (prevents root ball constricted)
Yeah, I tear the little bags so it will be easier for it to get out. I do this once the roots are getting strong.
I rip them about halfway down and (sometimes) alternate halfway up. Try to give the little fellas some room to reach out.