Using these addi Turbo circular needles is a breeze. Just thread your yarn through the needle and start knitting as you normally would. The smooth nickel coating will help the yarn move easily, so you can work on your project faster. When it comes to the non - standard sizing, make sure to double - check the actual size you're using according to the label. As for maintenance, gently clean the needles with a soft cloth to keep them in good condition. Avoid using harsh chemicals as they might damage the nickel coating. And when you're done with your project, store the needles in a dry place to prevent rust or damage to the plastic tips (for US 36 and US 50). Have fun knitting!