Depends on the veggies/fruits.
Hard-skinned ones (carrots, potatoes, beets, apples, etc), I use a veggie brush and scrub under running water. Set aside to air-dry, if I want them dry (rare).
Soft-skinned ones (tomatoes, peaches, nectarines, etc), I use my hand and rub lightly under running water. Set aside to air-dry, if I want them dry.
Berries and grapes and tiny tomatoes go into a small colander and I run water over while swishing the contents around. Set aside to air-dry and fluff every so often.
Leafy greens are plunged into the dishwashing pan filled with clean, cool water and left for a few minutes. Swish and lift in the same direction as rain would flow off the leaves. The dirt and such settles at the bottom. Once is usually enough for store-bought produce, but we get most of our produce from our CSA or backyard and those require at least twice. I use the "dirty" water in the backyard. I lay out the leaves single layer on a clean towel/rag, then lay another clean towel/rag on top and pat dry. (Technically, I ask my 9 YO to do this.

) This is for salads where we want them as dry as possible and we are fixing dinner right then. If we're cooking the greens, then we don't bother laying them out. The moisture helps them cook nicely. If we're fixing the salad greens ahead of time, just laying them out single layer on a clean towel/rag and air-drying works fine.