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Gather them into a bouquet....I'd do each type of herb separately...then tie them with some kitchen string, leaving long enough ends to tie a knot at the end and hang them from a kitchen cupboard handle or someplace in your kitchen. Hang them upside down, and when you come back from your trip they will be on their way to drying nicely.
To preserve without drying I've read that you can chop them & freeze them in an ice cube tray w/either water or oil...but I haven't tried that yet. I plan to at the end of this summer.

Enjoy your gift...how wonderful was that? :-)

I've done this several times and it works nicely, AFAIK:

I trim and wash the herbs from our garden and then sandwich them between two window screens (we have them from the downstairs apartment which we no longer rent). I put them on the table on the back porch, which, luckily is made of a metal mesh--the table not the porch, OK?
Within a couple of days the herbs are tried nicely. Depending on the quantity and size of your particular herb, you might want to move them around a bit each day to ensure even drying.
Still, considering the fact that you are going to be out of town, things should work out nicely enough.
Basil, I would puree or turn into pesto and freeze.

I had really good luck freezing oregano & thyme this last winter. I washed it, dried it well and rolled it up tightly in paper towels and then multiple rolls of plastic wrap. I was sad when I finally used up the last of the thyme in early spring. The rosemary should freeze well, too. As for the lavender, I like that dried upside down tied in bunches.

I tried the basil in olive oil trick last year, and it was great...I just put it in the blender and then divided them up in to tablespoon size servings and froze them in an ice cube tray. It was great to add to soups/pastas/etc all winter...