It is possible and very very easy! Gmail (Google Mail) actually assists in this by populating the fields for you in most cases. All you need to do is follow the directions! See link below for those! Please let me know if you need anything else!
Ah, I see, so you already have two "google accounts" as it were. 4 steps to complete that:
As for step by step, you may want to request a phone call, as doing that via this format will make it difficult, as we do not sit at our computers as if this is a job most days, we are all users of the website, just as you are. We only get paid when answers are accepted. :) Considering the variability in what you are trying to do, I can link up directions, I can even set them in order and type them all out here. If you are not comfortable following them, best to get on the phone. :) Let me know what you want to do! (A phone call request will open this to all available experts, so it may not be me you get on the phone!)