Skin prep
The first part of sticking a patch down involves preparing the skin for the patch. The most effective strategy seems to be washing the site thoroughly with a mild and pure soap—not something loaded with moisturizing oils but rather a something more like a glycerin cake or castile soap, for example.
Then dry it thoroughly. A hair dryer set on low is good for this, so that the site's not picking up lint from a towel.
Since putting a fresh patch on skin with dilated blood vessels from a hot shower can give us a nice little zap from the enhanced uptake, it's important to let the skin cool thoroughly.
Then it's time to apply the patch. Another session with a slightly warm hair dryer or holding a warm hand firmly on the patch for several minutes after it's applied, pressing it down fully and evenly, will help make the seal fully seat onto the skin.
As a final measure, a light dusting of powder will reduce the sticky along the edges and help prevent peeling from sticking to clothing. You may need to renew the powder daily if the adhesive tends to extrude a bit with time.
Do not use benzoin or the skin prep pads sold to people with ostomies to help their appliances stick to the their skin—those will make the patch stick, perhaps, but interfere with hormone transfer from the patch into your body, which sort of negates the whole effort.
Don't use things like acetone or industrial solvents to clean the area before application—that's going to alter the skin's uptake and expose you to risks from those agents. If you have to resort to heavy chemicals, you're not a good candidate for a patch.
If you want to be extra-sure you've cleaned the skin of all oils, one patch manufacturer suggests wiping the area down well with an alcohol wipe. Rubbing alcohol on a tissue or cotton ball will work equally well—you don't need to buy the expensive packets of individual wipes (although they're handy for travel use). Be sure to fan the area (or give it another whoosh with the hair dryer) to be sure all of the alcohol has evaporated and the skin is fully dry before you apply the patch.
Last, do make sure that the skin is well smoothed out before putting the patch onto it. One of our discussion group members shared a tip she got from her patch manufacturer: when applying a patch to the butt, sit down to apply it. This obviously will stretch things out and help assure that when you sit down later, you're not ripping it loose as your skin stretches. Clever, eh? That won't, of course, help with patches in other locations, but we can take a lesson from this and make sure we do smooth and even stretch out the skin if it's an area where there normally is considerable stretch in the course of our daily activities.
Problems
Some women find that they have a lot of body hair and this presents them with adhesion problems. For them, careful shaving may be necessary—careful because nicking or scraping the skin will also alter the uptake of the patch and then provide a risk of infection when sealed beneath the patch for that many days. This isn't something to undertake unless patches spring up obviously standing away from the skin on hair—women who have a history of bandaid failures know what we're talking about here. Don't get into this unless you absolutely have to, and even then, it's a good reason to consider another HRT form.
If that doesn't do it for you, then you need to look at the actual mechanics of the problem. If it's just edges rolling up from clothing, perhaps more careful selection of application location would help. If the powder trick doesn't work, perhaps taping down the edges would—that's okay, so long as the edges are well-sealed to begin with and you're just protecting them, not sticking failed portions of the patch back down. If you tape edges and the patch remains fully stuck down right up until the time when you peel it off to change it, you're okay; anything less than that total adhesion and you're fooling yourself (and not your body) with the tape. Don't take the tape off and replace it if it starts to curl, though—that's just going to lift the patch with it.
Some women who develop rashes under patches like to use an over-the-counter steroid ointment to facilitate that healing. We're not sure that any degree of irritation that takes drugs to recover from is being all that kind to our bodies in the long run, but in the overall scheme of balancing risks and benefits, we'll have to leave that one up to you. Remember, though, that different brands of patch have different chemical constituents in the adhesive, and so a rash from one brand will not necessarily happen with another.
After bathing
If you use body moisturizer after your showers, be sure to skip the place where you're going to put your fresh patch. It's fine to use a regular moisturizer, if it doesn't sting, where the old patch was. After all, that area is probably going to see another patch in a couple weeks, so making sure it's healthy and recovered is just right.
The dreaded goo-and-lint aftermath
Once you've removed the patch, you may be left with that unattractive lint-and-goo ring. This is also not the time to reach for heavy industrial solvents that aren't meant for use on skin that's just spent days underneath an airtight barrier. Instead, try a light coating of vegetable or nut oil or body butter. Let it sit on the goo for a few minutes, then shower. You should be able to wash the now-softened goo off with your usual soap and washcloth.
It still doesn't work
Finally, keep in mind that each patch adhesive is by definition (and patent) different. If one brand doesn't stick for you but you love patches as a concept, for goodness sake try the rest of the brands to see if another might provide better results for you. That's what samples are for.