When you dry herbs, you have a couple of options as to method. A bundle or bunch of herbs can be tied together with string - use about a dozen stems tied together to make a nice fat bundle - and hung in a dry, airy place. It’s generally not a good idea to hang them in direct sunlight, because they can burn and become over-dry. You can hang them from a drying rack in a warm spot in your house, and let them sit for about three weeks. This is usually enough time to dry most herbs - you’ll know they’re done drying because the leaves will crack when you pinch them.
Again, if you’re harvesting the seeds or blossoms, use the paper bag method. Secure the bag over the head of your drying bundle, and as the plant dries, the seeds and flowers will fall off into the bag.
Another method that some people like to use - and it works well if you’re in a hurry - is to lay the gathered herbs flat on a cookie sheet and place it in the oven at a low temperature. This will take a few hours, and it makes your house smell amazing. Be cautious, though - you don’t want to overbake your herbs, because they’ll be useless if they burn.
If you have a dehydrator, you can use that in a similar manner as the oven method - fortunately, a dehydrator works at a lower temperature than your oven, so the risk of burning your leaves is lower. Be sure to check them periodically to see if they’re done drying. Again, when the leaves crumble to the touch, they’re ready to go.