The first thing to do is to focus on the result that you want to achieve. Do you need to gain weight or lose weight? How do you want your body to look? The reason this is so important is because every diet choice affects how your responds. Some important questions to consider is:

How many calories will I get each day by following this particular diet? And how much calories do I need to lose or gain weight?

Am I getting any nutritional value from this diet program? For example: adequate minerals and vitamins, carbohydrates, protein, fiber and fat.

And most important is Can I stick to or follow this diet plan?

Some diets to search in google would be a fixed menu, exchange type where you choose from different food groups, prepackaged meals and formula diet just to mention a few.