Also, take the long view. By that I mean that those skills(z) are something that grows over time and never stops accumulating. You will be slow and make mistakes at first and that is OK. Be willing to make those mistakes, tear them out if need be, and work at it to get it right.
There are two elements to those skills in my mind: the ability to properly use the tools, and the knowledge to put the pieces of a project together. Things like habitat for humanity will be great for taking the mystery out of a house, plus helping a good organization. A house is nothing more than some sticks, boards, pipes and wires stuck together. Helping with experienced friends will help with the putting pieces together.
Sam Clark's Independent Builder is a great general reference for the big picture of how houses are put together and how to think right. It won't allow you to step out and build a house, but it will provide a good foundation for going to the specialty books on framing, wiring, plumbing, masonry, etc as you need them.
Most importantly, jump in. Each project completed will give you new knowledge and skills making the next project easier, and more efficient. Pretty soon your friends will be asking to help you with projects to learn from you.