iOS 11.2 beta 4 is released now. Get the direct download links for all ipad models here. Just tap on the download button to start downloading the ipsw file automatically.
For iPhone Users. Click Here .
This is without the USE of developer account or UDID. So just use this method to bypass the activation and use it freely.
How to install ios 11.2 beta 4 iPSW Without Developer or UDID
To install follow this process