Make a taming pen with stone gateways, 2/4 on each side, 1 on the front side, and fill the back side with one doorframe with door and the rest walls. Place a large bear trap in the middle. Trap the allo in the pen in the bear trap so that you can safely close the front side gateway (the rest should be closed. If needed, kill the others. Make a foundation with a staircase on the backside. Now easily knock at tame the allo. This probably works for more dinos but only tried with allo.
They say beaches are low resource/low threat areas right? WRONG! I used to live in one close to a cold region and some of those decided to run around the beach killing everything there. Fine, I hid from them in my tatch base and once they were far enough I thought I was safe, that until another freaking pack started doing the same. I hid my Dilo (Galinha Punk, my beloved only tame, great companion) inside the base and ran through the ocean to hide on some stones. And this was way before they cold spot me. Result: I had to hold my tears and watch in horror as they destroyed the little base I put on all my effort to build, killed my poor boy and kept going like it was nothing! Their levels were way too high, I couldn't fight them, but I was so sad I tried, died, couldn't respawn there cause I had no bed anymore, and couldn't get my stuff because they were near. Of course i waited until they went away, and of course wild dilos destroyed the rest of my stuff. I shall have my revenge!
The Allosaurus is a very useful creature, they can be used for meat harvesting, base guards, kibble, etc. Allos are also very useful for bosses, I would recommend mixing some of these (preferably mate boosted) with rexes for the bosses.
The Allosaurus is a pack-hunting theropod that's smaller but faster than Rex, and larger but slower than Carnotaurus. When in packs of 3 or more, the highest level Allosaurus will become the pack leader, emitting a red aura and making it stronger in battle.