Compost Vegetable Scraps
Take a harvest basket and a compost bucket out to the garden with you so you can immediately begin cleaning the produce you harvest. Remove outer lettuce and cabbage leaves, trim carrot and beet tops, and otherwise tidy up produce and put the scraps in the pail for an easy trip to the compost pile. Toss an occasional shovelful of soil between layers in your compost pile and turn it weekly. You'll have finished compost in a month during these warm days of summer.
Thin Peppers and Tomatoes
Pepper branches heavily laden with fruit are prone to breaking. Harvest some of the peppers at the green stage to allow the remainder to ripen safely. Secure heavy tomato branches to supports and harvest some of the almost-ripe fruits to prevent stems from bending and breaking.
Harvest and Freeze Berries
Even if you can't eat them all right now, take advantage of the abundance of fresh fruits and berries. Freezer jams are surprisingly easy to make, and even regular "canned" jam is pretty straightforward and makes a great gift. At the very least, freeze some berries for later use; simply spread them out on a cookie sheet and place them in the freezer. Once they've frozen, pour them into freezer bags and seal.
Store leftover seeds in tightly sealed glass jars in a cool, dark place. Collect seeds from early-maturing plants, such as columbines, and either replant immediately or place in jars for storage. You can also allow the plants to drop their seeds naturally, then transplant new plants next spring.
Remember the adage, "mow high, mow often." Leaving grass blades a little longer will help crowd out weeds and also make the lawn more drought tolerant. And don't forget to leave the clippings so the nutrients they contain will be returned to the soil.