Welcome! An answer to that would fill a book- and there are many! I suggest going to the Disneyland main forum (this is the Community forum). Just start reading through the posts. Then when you have a specific question ask and many will be happy to help.
As a general recommendation, the best suggestion I can make is get there before opening. Morning is the best time for seeing the parks before they get crowded. I also suggest a 4 or 5 day park hopper. This will allow you to have time to take afternoon breaks and not wear yourself out.
Hope that helps you a little.
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