When it comes to ASL which hand should I use?
Most teachers will tell you to use the hand you write with as your dominate hand, I suggest learning all signs and fingerspelling on both hands, in case something happens to one hand you'll still be able to use your other hand without it feeling awkward. Always use your dominate hand for ASL but take some time out to learn signs on your other hand for emergancy back up.
What is the best way to wear heels?
For short dresses wear flats, for long dresses wear heels, heels in a short dress is make your dress appear even shorter so flats are suggested for a short dress, heels will make a long dress look classy and keep it from dragging on the floor, plus it will add height if you're short.
What is the best way to change the background to my photo?
Use the crop wand, and crop out the background and replace it with a new background of your choice.