How to set goals?


I’m new to scs and I was wondering if there were any videos or booklets on how to properly set goals/ deadlines? I’m a little confused about a couple of things.

How do I choose what route or steps are the best to take to reach my goal? Do I just go off of what feels right and seems like the most logical answer and then leap?
How specific should my goals be? I feel like the more specific they are, the easier it is to actually make a plan for them but at the same time I feel like it puts limits on the different routes to my ultimate goal.
How do we decide on a reasonable deadline for goals?

Thanks in advance! 🙂