How Can You Reduce Air Bubbles In Your Resin Pieces Or Resin?

Pour it thinly from a height if you have a steady hand. Less air gets in that way. Beware if you are outside and its windy though! It can blow the resin around.

Placing your resin bottles in warm water for a few minutes before starting helps to reduced bubble while mixing

You'll always get micro bubbles with resin, so yes stirring slowly will help lessen the amount, but it'll still be there. You can let your bottles sit in warm water for about 10mins so both liquids won't be too viscous and from there you can measure out the amount you need and mix slowly.

Also a heating tool will be great to help pop some bubbles as well as a utility lighter. Just keep the flame to a minimum that way you don't burn your resin.

I mix it slowly, let it sit for 5 minutes, and then use a tooth pick and/or straw.

I find mixing slowly and letting the mixture sit for about 10 minutes after mixing helps. Usually I'll apply heat only after that because most of the bubbles would have risen to the surface. HTH!