Hi KimberleyA! Having a chequered work history will be an asset for you - you can interface with different areas of a business with some experience. It may be difficult to head into UX without significant crossover in at least one particular area. Your sales and teaching background will possibly be most useful there.
Doodling and sketching when problem-solving can help engage the visual side of your brain. It might feel a little forced at the beginning, but if you stick with it you'll find yourself doing it naturally. There's no right or wrong, so go with the flow. =)
If you find yourself working in a UX role that is associated with web design, then having some basic web design experience yourself will be pretty important for understanding what is possible and how the bits fit together. There are some great web design courses available online via places like Learnable, Coursera or Udemy. Web design and UX are of course pretty compatible, so you can practice your UX skills while learning and getting experience with web design.
Some books like [A Project Guide to UX Design are pretty UX focussed, so you'll get the benefit of both. The Principles of Beautiful Web Design(http://www.amazon.com/gp/product/0321815386/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=0321815386&linkCode=as2&tag=uxma09-20) pitches itself with the phrase 'You don't need to go to art school to design great looking web sites!' and covers the basics like web page anatomy, grid theory, psychology of colour and colour palettes, typography, where to source legitimate images, file formats and resolutions, etc.
Borrowing intelligently from other people's work (without ripping it off) is also a good way to build familiarity with layout and interaction.
Practice, practice, practice. And like ASHM said, if you're having fun with it you'll move a lot quicker!