Optimal deployment locations:

Parking garages

Highway overpasses before the morning commute (be sure the banner isn’t too long and won’t get caught on passing semi-trucks)

Buildings’ roofs

The balcony level of a church, movie theater, coliseum, auditorium…

A banner drop can enable you to get a simple message out in dramatic style to potentially thousands of people. They can be most effective in crowded environments during special events, or to accentuate and clarify an action taking place nearby.

You can make a really huge banner by sewing together smaller pieces of cloth; be sure they won’t come undone, though! Double- or triple-stitching with exceptionally tough thread is probably necessary. When deciding on the size, keep in mind the way it will be transported to the place of use, the dimensions of the area where it will be deployed, and the distance from which it will be seen.

To decorate your banner, you need not be an accomplished artist; simply draw a scale model of the image or statement you would like to paint, separate that image into equal sections, mark off matching sections proportionately on the banner, and use these as guides. You can trace the lines first with chalk. You will probably need an open space outside the surveillance of the authorities to work in, since when your banner appears you won’t want it—or yourself—to look familiar to any agents of law enforcement. The paint will almost certainly soak through the material and onto whatever is beneath it, so be prepared for this as well, in terms of security as well as tidiness. Be careful above all not to spell any words wrong (!) or bunch up your lines of text near the end, and make sure your colors are striking and high-contrast and your images similarly easy to discern. Don’t use spraypaint to paint your banner unless you are especially talented with it.

There are many options for how to attach your banner, but it largely depends on the location and the material. The best (but most time consuming) way to drop a large banner is to fold the top of it over rope or chain and sew the fabric around it, creating a seam. This allows the banner to be straight all the way across the top, and not sag in the middle, or rip off the corners due to stress. If you are putting your banner somewhere where you can tie all four corners to stationary objects, you can bunch up the corners and tie tight knots to each one. But if you are expecting the bottom of the banner to dangle at all, it’s important to tie some sort of weights (filled water bottles work well) to the bottom so that the wind doesn’t tangle it up and obscure your message. There is no single good answer for this — just be sure to think strategically about the best way to keep your banner stationary and resilient.

For deployment, a team of two is usually best, unless you need a third person to be a getaway driver. Pick a time and location where the visibility balances out the risk. You’ll have to get the banner there, somehow: if it’s a freeway overpass, you could pull over and hop out, or just run up the ramp with it if you don’t want to risk a license plate number being taken; if it’s at the top of a busy corporate office building patrolled by guards during a terrorism scare, you’re probably better off not carrying a huge, suspicious parcel up in the elevator—are there stairs in the back? If you find an abandoned building that you can get in and out of easily enough and that isn’t frequently checked upon, and you don’t have anywhere else to work, you could theoretically smuggle in the materials and go through some or all of the banner-making process inside before dropping the banner(s) off the roof—and securing the hatch behind you with your own padlock for extra longevity.

The hard part is always going to be getting out of the place after you’ve dropped: generally speaking, the more conspicuous the location is, the more people know immediately that you’re there, and the longer it will take you to get down and out—and the less likely you are to have any kind of crowd cover as you do so. Dress as non-descriptly as possible (or as maintenance employees!), and practice moving quickly up and down stairwells without getting suspiciously out of breath. Check the area out ahead of time; if you’re going to be on security cameras at any point, bring a change of clothes, glasses, a hat, a reversible jacket, or other accessories to disguise your identity.