FUN!!!
Don't worry too much about the accuracy. It develops with practice.
Don't worry too much about what's an "appropriate beginner" project. All the skills needed for any project can be learnt step by step by diving in and doing them. Making a small practice square of less precious fabrics can help you free up and give yourself permission to explore. Fabulous tutorials are available online (quiltingboard, youtube...) and in books. Quiltingboard is a superb support network for practical questions.
Remember how kids play? Having fun and learning at the same time. Allow yourself to play with some fabrics (not the ones you find too beautiful to cut right now). Make a small practice square or two or three, it will teach you loads and tell you what you most love doing at this point. Then from your own experience decide what challenge you want - a bigger or smaller project, simple or intricate... Some people like following patterns. Others prefer to make up their own thing (I'm one of those, I actually find it easier). Either is fine. Go with what you love and it'll be worth doing.
(Can you tell I'm self-taught and not afraid of trying whatever I fancy? If I can do it, anyone can.)
Did I mention FUN!!!