I use the cardboard boxes for stuff that I don’t use real often and try to get clear plastic boxes for more often used things, so I can see what’s in them. If you’re stuck with those black Depot boxes, white or yellow paint pens are great for labeling. I kind of prefer yellow. For me, I’ve got to see the labeling, or the stuff, at a glance.

I’m also reorganizing my roll-chests and stuff disappears as soon as the drawers close, so I’m using a tape type label maker pretty extensively on them.

Another thing I’ve learned the hard way is to not over or under sort stuff, e.g. nails, screws, bolts. If you have like things together, you can dump out a container of small machine screws, nuts & washers, paw through them for what you need and shovel the rest back into the container - same for boat parts. The key is “like enough” without overdoing it.

The wide black felt markers work well on standrd brown cardboard boxes. For big boxes, the really fat ones are good.