Here you will find a complete set of documentation including installation, configuration, permissions and usage for SimpleClans.
1) The Wiki
You should always check this wiki carefully for the answer to your question! Even if it seems hidden, it may be here!
2) The Discord
If the wiki does not have your answer, feel free to join the discord server to ask for help.
If you believe you have found a bug in the plugin, feel free to make an issue on the issue tracker! Bugs will be looked into and addressed at the earliest opportunity.