While it is extremely important to stir the resin and hardener thoroughly for 3 minutes or ArtResin may not cure properly, you really can't overstir. Just remember that you have a 45 minute window in which to pour before the resin will start to cure and become to thick to work with. So when you stir, make sure you go slowly and methodically, and that you scrape the bottom and sides as you go. Try not to whip the resin because that will just induce more bubbles than you need. If you detect bubbles in the ArtResin epoxy resin after stirring, you can simply torch them out with ourArtist's Torch.