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Five tips, because that is what all the magazines do.
And because it only looks good on camera when you count on one hand.
But I will throw in something else here at the beginning. Not a tip, but actual advice!

If you don´t know your way around working out or healthy eating, go talk to a professional. Get a medical check, book a PT, or even trust an experienced friend. But please have someone that knows his stuff help you with how excercises are actually done.
Do not, by any means, just do online videos if you have never worked out before. And, no matter how fit and toned that person looks, don´t take workout advice from someone online that isn´t a certified PT (or yoga/pilates/whatever instructor).