Mix a solution of 5 parts water, 1-part alcohol, and a squirt of liquid dish soap. Then, spray all leaf and stem surfaces until they are dripping wet. It is a very messy task, but unless you get complete coverage and make direct contact even with the ones you cannot see, the survivors will reproduce, and the infestation will return. Be sure the solution runs into the crevices where leaf stems attach to the main stems.
If you just treat the visible mealybugs, you will miss the translucent and nearly invisible juveniles that will mature and reproduce. Thus, it is important that you spray ALL leaf and stem surfaces until they are literally dripping wet. Thorough coverage is the key to successfully eradicating the problem and avoiding repeat treatments.