To minimize dust, hose down your garage floor and anywhere else that dust could get kicked up. It also helps to clean up the over spray on the floor as well. Make sure you have a fan blowing out of your garage as well, this will pull dust and fumes away from where you're painting. Other than that, dust is going to be part of your paint job when painting in a garage at home.
Some people build simple paint booths in their garage. You can frame in all around your garage about 24" in, then cover it with plastic, add HVAC filters and a fan and you have a redneck paint booth!! Pretty simple for those DIY guys. There is a youtube video of how to do it, some are fancier than others depending on budget.
Make sure you save some $$ to pay a pro to pin stripe the color line.
Car looks good, great job!