Fully exit Steam then relaunch it - don't just x it out, fully restart Steam
Right click on Aimlabs in your Steam Library > press Properties > press Betas
At the top right next to Beta Participation, select beta - beta test branch
Steam will trigger an update to Aimlabs that will download the beta
Once the download is complete, Aimlabs will have a [beta] signifier next to it in your Steam Library, letting you know that you're currently on the beta
To leave the Beta and go back to the normal version of the game, follow the above steps but instead of selecting beta - beta test branch, select none
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