First, I start off by taping down some wax paper to my surface using masking tape. This prevents any accidental glue from getting on your surface and also allows your stamps to be easily removed once the adhesive has dried. Then lay your stamps face down onto the wax paper surface. **If you have unmounted the stamps from wooden blocks, be sure all the foam has been removed first (you can usually easily rub it off with your finger, or use goo-be-gone or an adhesive remover to get any remaining foam off the rubber). I also make sure my stamps have been trimmed closely to the images and I cut apart any sayings before I add the glue. I can always line the words up just as they were originally intended, or stamp them in a different variation on my project when they are cut separately.
The next step is to be sure to wear the disposable gloves. I have found I like to only wear one...on my left hand so that I can use that hand with a toothpick to hold down the stamps while I paint on the glue. I am right-handed. Trust me, you don't want to get this glue on your hands...it's hard to get off!! :)
Then I squirt some glue on the backside of each stamp and spread it out with the foam brush. On smaller stamps, I have found you can use the paintbrush to "pounce" the glue on. If your fingers get in the way when you are holding the stamp still, you can use your toothpicks to hold it down. I usually paint on a medium heavy coat of glue. Don't want to drown your stamp in glue, but as long as it's fully covered, it will work.
As the glue dries, you will see white spots where it is still wet and they will turn clear when the glue is completely dry. I usually leave the stamps out for a few hours just to make sure the glue is completely set and had time to get fully tacky.
Here is a picture of my stamps after they have dried (and had time to get tacky) Again, I usually wait several hours to let the glue fully set. You can see how it's dried clear and kind of "shiny" where the adhesive was painted on. Before I put the stamps on my storage sheets, I usually stick them to the back of my hand to tone down the stickiness a bit...they are quite sticky when they have fresh adhesive on them. **If the stamps ever lose their stickiness down the road, I simply repeat the same process and add another thin layer of painted on glue. So far, I haven't had to do this to many of my stamps. The dried adhesive will last for a good while. Also note that sometimes you will get excess glue on the front or sides of your stamp by accident...I know I'm a messy painter at times. :) Don't worry about it...just rub it off with your fingers once it is dry. Remember to try not to touch the wet glue with your hands...it's a pain to get off. For some reason, the dried glue is easier to remove. It's kind of like rubber cement.
Hope this helps answer some of your questions about my adhesive solution. The Tack it over & Over is relatively inexpensive (around $5 or under a bottle) and that lasts a LONG LONG time. I have found mine at Michael's craft store in with the other adhesive/glue bottles.
If you have any questions, just let me know. :)