The simplest technique is to stick the flowers in a loosely closed paper bag and let it sit in a dark well ventilated place for a few days.
First, cut the stem just under the lowest branches, and turn it upside down. If you want, you can remove any remaining sun-leaves at this point, but I prefer to leave them on. Hang the plant (still upside down) in a dark room or closet, and use a small oscillating fan on LOW to keep the air moving. Close the door, and forget about it for seven days.
At this point, take the plants down and clean them, trimming away anything you don't want anymore. They will still be a little moist, but an hour or two exposed to the air should take care of that. The result should be a smooth, pleasant flowers.
It's very important that the plant receive absolutely no light during the initial curing process. This allows the chlorophyll to break down and evaporate with the water. Leftover chlorophyll will leave a chemical smell (kind of bleachy). Also, if you don't circulate the air thoroughly, the flowers can ( and likely will ) develop mold, which causes it's own set of problems.
As a reference point, hanging the plant upside down does not increase the scent if the flowers. It does, however, allow the plant's natural oils, which evaporate more slowly than water, to concentrate in the glands, keeping the flowers fresh and fruity for longer periods of storage.