What do people use for a windscreen while cooking on trips? I’m guessing a decent amount of fuel ( and time) could be saved by using one but I’ve always thrown in an extra canister or 2 so we didn’t have to worry about it.

Strongly considering upping my game in this area. Is it worth it? If so, how do you do it?

I use the sheet aluminum windscreen that came with my stove. Others use sheet steel segments that are hinged and pinned together.

In the case of my OEM screen, I try to wrap it tight enough around the pot and stove that it creates a fairly tight seal and crimp it onto itself to stay put. I used to use a paperclip but then the paperclip kept getting lost. Occasionally I have to use the windscreen upside down so a detachable pot handle can be used.

My stove is a MSR Windpro, which is awesome because it's a remote canister stove which can be run 4 seasons. If I were out in the dead of winter, though, I'd use a different (white gas) stove.

Edit: Is it worth it? Yes. Wind robs heat, which in turn causes you to burn more fuel and dinner takes longer to cook. Or the coffee takes longer to be ready.

I collect MSR stoves and have a pile of MSR windscreens, aluminum flashing material describes it well. with a Dragonfly and fresh baked biscuit.
I have a few folding panel screens for canister top stoves, High Rock Windscreen with canister top stoves do NOT use a wrap around screen, this can overheat the fuel canister with disastrous consequences.
Some stoves come with a specialized screen, MSR Firefly, Primus Essential Lite.

butthead

Yes, it's worth it. You didn't say what kind of stove you had, but for a sit-on-top canister stove I used one of the folding screens like butthead linked. Just put it around the windward side of the canister, but don't enclose it since overheating the canister could cause explosion. For a remote canister stove you could do like mirth. I use a JetBoil Sol which is already protected by the flux ring. I usually set it up on the fire grate and protected by any rocks there. If unprotected and really windy, I might set it on the ground behind any rocks there.

It's worth it to follow all the suggestions out there for minimizing fuel use and also keeping track of your usage so you can better know your needs. I can calculate mine pretty closely now and no longer carry extras "just because", although I do add a 10-15% margin of error.

Get some sheet aluminum, it’s way thinker than foil. It can be bent many times before breaking.

While my Optimus Vega (remote canister) came with a nice windscreen, a couple previous stoves didn't. I first made a windscreen for one of those with aluminum flashing, but didn't like the stiff, springy material. I had much better performance (and easier storage!) with material cut from a turkey roasting pan ($1). Use a rolling pin to flatten any ridges or embossed print, cut to length & height needed. I also suggest folding each edge over by ~3/16" and flattening with the rolling pin to eliminate any sharp edges.

TZ

I learned about using stove pipe to make a screen. Mostly I use a folding aluminum screen. They make a big difference.

I use a couple sheets of thin plywood. Which also double as filet board, card table, fire fan, etc.

Type this into a search on Amazon:
"folding windscreen for camp stove"