It indeed depends on the plant. glosso has to be planted with tweezers and hours of patience.
java fern should be tied/stapled/wedged in place and allowed to root above the substrate.
crypts do best with a fert tab placed underneath to minizme crypt rot
anachris can be jammed in without any finesse, or left to float.
most basic stem plants, just press the stem about 1.5-2 inches into the substrate, tamp it down around the base to secure, and move on.
swords with very long roots, you can trim the roots and plant it, spread em out a little, and they'll grow back quickly.