Key combination

Two ways

1. Left Bracket Key [ to Decrease Brush Size

   Right Bracket Key ] to Increase Brush Size

2. by holding Option +Control + Left Clicking + Dragging the mouse left or right.

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

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