Sewing a scant 1/4 inch seam is important. Measure twice, cut once. Use only one ruler when measuring. It's best not to use the markings on your cutting mat. They will wear out sooner if you use them. When buying standard type rulers it's best to use the same brand. Different companies, different measurements. When in doubt, check the measurements with different rulers.
Change your rotary blades, don't cut with dull blades. A good source for cheap blades for the 45mm is Harbor Freight. They are called carpet cutting blades. They do tend to be sharper IMHO than our regular rotary blades so be aware and be very very careful. Don't cut fabric when you're tired. Quit, then start again after a good night's rest. Ask me how I know!!
Learn how to prepare your fabric. Wash, dry, iron. Learn when it's good to use starch, spray sizing. Many have switched to a new product for fabric treating when ironing, called Best Press. It's wonderful. Comes in different fragrances, and without. It's definately worth the money. Buy it with discount coupons whenever possible.
Spend time on You Tube. It seems there is a video for anything you might want to learn about.
You've done one of the best things by coming here and being a member. We are just one click away from trying to give answers and help in any way.
Search for guilting groups in your area. Check out any LQS, local quilt shop, for classes and guidance.
Don't be afraid to ask questions.
Good luck, enjoy the journey of quilting.
Pam M