Setup the Remote API on your server - follow this guide if unsure how to set up: https://pingperfect.com/index.php/knowledgebase/317/Space-Engineers--Use-the-Remote-API.html
Connect to your server using the VRage Remote Client.
Join your Space Engineer's server.
Then you can use the Promote button in the Vrage client to assign Admin rights.
Once promoted, any admin can start using the admin menu directly from the game client.
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