With having started a small business making tote bags, stickers and magnets, I had some trial and error with products used but have since found the holy grails I will continue to use
First, is the machine itself! I have the original maker but depending on the items you are planning to make, each one has its own benefits to suite your needs
Cutting Machines | Cricut Shop
You don't need the best of the best for a printer if you are doing print and cut projects, the ECO tank printer is perfect for this
Epson EcoTank ET-2800 Wireless Color All-in-One Printer
The standard grip mat is great for so many projects, I always have one of these
StandardGrip Machine Mat, 12" x 12" (2 ct)
I personally use these mats for my stickers and some other lighter projects
LightGrip Machine Mat, 12" x 12"
Blades are important depending on what you are cutting, I use the standard for most projects but also use the deep blade for a few
Cutting Machine Blades
I have tried many a brand of vinyl's yet always come back to the Cricut brand, it weeds the best and lasts the longest
Premium Vinyl™ - Permanent
Iron on from the cricut brand is again a personal fave, I have never had any issues with any of the colours used
Iron-on (HTV)
Love the sparkle iron on for an added touch to my tote bags
Cricut Glitter Iron-On Heat Transfer Vinyl (HTV)
Infusible ink is some of my favourite to use for a more permanent touch, especially for anything that will end up needing to be washed
Cricut Infusible Ink Transfer Sheets - Variety Pack