Mmmmm - late summer picnics!
Crusty bread and good cheese - yum!
Tomatoes can be a bit messy, but cucumber cut into sticks travels well and is fun to eat - take a small pot of good mayo. Boiled eggs are easy to eat, too. Don't forget the salt.
Fruit? whatever's in season - plums, apples, the last apricots or cherries - depends where you are, love, here in Yorkshire it's just blackberry time, and our friends brought us a bag of their first apples. Of course, picking your own fruit is nice too.
If you're a good cook, make a quiche, cookies, or whatever - but anything too sweet can leave you thirsty.
Juice or water, of course, more refreshing than alcohol.
Take plenty of paper napkins, some wasp/skeeter repellent - incense sticks work ok - and a damp towel in a plastic bag for sticky hands & faces.
Have fun!