Beta registration for Android Q is going live as we speak. Some have already been able to register their devices and receive OTAs, while others are still seeing the old landing page. Either way, if mucking about in ADB or unlocking your bootloader doesn't appeal to you, this method is a bit easier.

Those of us here at AP that have managed to register devices are reporting that the OTA downloads are as slow as molasses. Paired with the fact that we can't all access it, YMMV. The page for registration is here, and all Pixel phones should be compatible. You'll need to agree to the beta's terms, but once you're signed up, it's all automated.

Once you're in, you should shortly receive a notice that an update is available for download on the device selected for registration.

The Android Q updates will be large, so you should probably aim to be on Wi-Fi when you pull them down. If you've never done this before, it might seem like a nerve-wracking process, but don't worry. Compared to manually sideloading the OTA via ADB, a lot less can go wrong.

Source: Android Q Beta program registration