1) Choose : I want to use HumHub for: "Skip this step, I want to set up everything manually"
2) Install with sample data i.e TICK Set up example content (recommended)
3) Move all the images of uploads/profile_image/ from manual to zip.
4) PHP REQUIREMENT LINK : http://docs.humhub.org/admin-requirements.html#server-requirements
5) Upgrade Notes: https://docs.humhub.org/docs/admin/updating/
6) Upgrade supports step by step upgrade from previous major upgrade only. So always update version number in info.xml in every major version.
7) Download upgrader package from https://github.com/humhub/updater always take the latest package and update our upgrader.zip (We can cross check this package by downloading from Administration --> Modules --> search for "Humhub Updater" and download. This new package downloaded in protected/modules/updater.
"Update Humhub" icon stays post upgrade.
8) Keep guid same in SQL for all tables.
9) Important note : We have used upgrader module version 2.1.12 for upgrade from Github https://github.com/humhub/updater/releases/tag/v2.1.12 (This is needed while upgrading 1.14.x to 1.14.x and to 1.15.x as well). However for upgrading from 1.15.x to 1.15.x we need to use the latest upgrader available (currently 2.2.x) https://github.com/humhub/updater/releases
(On vendor intimation via email)
10) Timezone : Select America/New_York from dropdown (since 1.17.0). Also keep the same in php.ini.
11) A humhub community member has asked us over ticket to enable pretty urls and hence we have copied common.php and .htaccess files. 
https://docs.humhub.org/docs/admin/installation/#pretty-urls