As I'm sure you're aware, glyphosate is usually only appropriate as a weed killer on your property if you're looking to kill all vegetation in/around where you spray it. For example if you wanted to "nuke" your lawn by killing all the grass and starting over with new grass. It's a non-selective herbicide in this context, it kills everything.
If you've got some dandelions or thistle, and it's not out of control, the nice safe way is to pull them up by hand or, if they're between pavement cracks, pour boiling water on them.
Broadleaf weeds growing in your lawn that aren't easily hand-pulled can be killed with a selective herbicide like 2,4-d. Tough underground vine-style weeds like creeping charlie or wild violet will need a selective called triclopyr. Crabgrass is best killed by a selective called quinclorac. Yellow nutsedge requires a selective called sulfrentrazone or another called halosulfuron.
Selectively kill the weed infestations as best you can, get rid of the bad ones before they go to seed, and focus on the health of your grass -- in most parts of your lawn, healthy grass will out-compete weeds.
I get a little paintbrush and paint the leaves of each dandelion with round-up - that ends up killing them but largely leaving other plants alone.
Glyphosate is extremely effective as a targeted weed killer. It only impact what you spray it with. It does not teleport from one plant to another. It's also not strong enough to kill heathy mature plants with a small amount of overspray.
Don't spray herbicides everywhere (unless you're certain that's what you want or need).
Instead, just spray each weed a little bit, right above where the leaves connect to the stem.