Aphids attacked my chile pepper plants. I got rid of them by spraying the plants with diluted soapy water in a spray bottle. Use dish soap with a lot of water. Knocks then right out.
My friend and I (she is a Master Gardener) discussed soapy water. She says you have to be careful with dish soap and you need to wash it off a day or two after applying. It apparently plugs the leaf pores and can damage or kill the plant.
You can use white or apple cider vinegar; both contain the acetic acid you need for it to work. Use one part vinegar and three parts water, regardless of the measurements you use. This ratio will dilute the vinegar enough to reduce the harm to your plants while still being strong enough to kill aphids.