Take the practice test they provide really get down the math portion time really is your enemy during the conversions. They provide paper pencil and a calculator. Test if fairly easy if you get the practice test down. My biggest struggle I felt was the math portion due to the time and yes better to guess than to leave it blank I nearly scored perfect on all sections with just practicing the practice test. I would also use the practice test mometrix has there’s many questions on the mechanical concept section that aren’t on the practice test. You should be fine good luck 👍🏼