I found that if you use a Q-tip and rubbing alcohol you can dab the larger ones to kill them asap and prevent them from producing any more. Then I have used trounce to spray the areas where they sit to kill the little ones.

I had to do this for some African viloets I was given. Kept them isolated from my other plants until they were clean.

I would simply enclosed the plant in large plastic bags, spray pyrethium based insecticides and let it stay that way for a few hours. This way, you capture all the bugs.