Losing weight for health reasons?

I need to lose about 15-20 pounds for health reasons. My plan was to go to at least 3 aerobic classes a week. What else can I do to lose it effectively and swiftly. I am going to school so I don't have a lot of time during the week for more than 3 aerobic classes. Any tips for eating routine? I was thinking like eggs or a breakfast shake in the mornings and a little lunch (like a bar) and then just a regular well rounded dinner...will that work? Tips please :)
Losing weight for health reasons?
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