Every year dozens of parents ask me "What is the best way to break in a glove?" So I thought that would get on my soap box. As I climb up here please note these are my opinions...so the gospel according to Coach Bale. Haha! There are various ways to break in a glove. I will try to touch on all of them but anyone that knows me would consider me to be a purist. Just use the glove. No heat, no steam, no oils, no conditioners. I know that some of the newer more expensive gloves are very stiff out of the box but with some use (you know playing catch) the glove will soften and begin to break in for the user.
Breaking in your glove by using it greatly diminishes the risk of damaging the leather. Just play catch! A lot of catch. Squeeze that sucker into submission. Sooner rather than later the glove will begin to soften and become that extension of your non throwing arm that you want it to be. Anytime someone asks me how to break in a glove I always say "Just use it" In my opinion all the other methods are dangerous to the leather and will shorten the life expectancy of your new glove. The more you use it the better it will feel. So if you have a new glove go play catch. You can also use a ball mallet when you can't get into a facility or outside due to weather. You can put the glove on and then pound the pocket with a ball mallet. You can make a ball mallet or buy one. Mizuno sells a nice one pictured here.
Some glove people will tell you to steam the glove. Steaming the glove will expedite the softening process and allow the leather to relax sooner making it easier and quicker to break in. Not a big fan of steaming. One reason I don't like steaming is that steam is very hot water...I don't want to put water on my leather glove. Just sayin'.
Some people will use leather oil or leather conditioner, I find that these can make the glove too heavy. There is a time to use those products but usually at the end of the season when you are putting your glove away for a couple of months. TIP - apply glove conditioner so the the leather doesn't dry out. Apply at the beginning and end of the season and if your glove gets wet let it dry naturally before you apply the conditioner. If and when you use these it should be done sparingly. I typically will apply conditioners to the laces and some of the areas that appear dry or slightly worn. My favorite glove conditioners are the Wilson Glove Conditioner and the Nokona Classic Glove Conditioner. When you are conditioning your glove be sure not to overdo...a little goes a long way. Oils you should stay away from include petroleum jelly, olive oil, mink oil, and linseed oil.
I have heard that some people have dunked their glove in to hot water for 15 seconds then manually work the glove. Lets try to stay away from water. You wouldn't leave your glove in the rain so lets not intentionally put our glove in water. Just seems to me to be a quicker path to the glove grave.
Lastly the Oven Treatment. Not sure whose bright idea that was but wow! Conventional or Microwave ovens can do irreparable damage to your new leather baby. Not to mention that microwaving or baking your glove can be dangerous, like starting a fire. There is also a risk of some gloves have small metal parts and could create a fireworks show in the microwave and burn the leather in a conventional oven. So unless you are planning on eating your glove, keep it out of the oven.
Coach Bale
Thanks to www.baseballmonkey.com for a lot of this content.