"Pinching" your annuals is one of the best things you can do. Pinching will change a plant from straggly and wimpy-looking to stocky and bushy.
To pinch annuals, simply remove any straggly, overly long stems, either with your fingers or scissors. It is also a very good idea to pinch off the first flower buds that form on your annuals to encourage branching rather than flower production. The initial loss of a couple of blooms will result in even more flowers in a few weeks.
Pinching can be done at any time during the active growing season. I know that, already here in early July, my marigolds are getting a little leggy, so I've been pinching them back. As you can see from the photos, I've merely removed that long, central stem and flower, which will encourage more side shoots to develop. In a few weeks, this marigold will be full of blooms.
So, go ahead-give your annuals a pinch. They'll like it! ITGO