Installing mangosbot can be tricky but easy if you are famillar with the original cores. Although this guide is for Trinity branch, it can used with others as well.
1. Checkout the code from the appropriate branch. There is no core changes, so build and install it using instructions provided by the core team.
2. Configure AhBot and MaNGOS-Bot by putting ahbot.conf and aiplayerbot.conf to your config directory (where worldserver.conf is located). Feel free to change any value although the default ones are fine.
3. Apply sql/characters_ai_playerbot.sql, sql/characters_auctionhousebot.sql and sql/characters_ai_playerbot_names.sql files to your characters database.
4. This is not required but recommended. Add "Logger.playerbot=3,Console Server" and "Logger.ahbot=3,Console Server" to worldserver.conf.
5. Run the server. The first run can be slow as a number of random characters will be created. It is recommended to init them all at once by running "rndbot init" console command.