Create a new GUI with /gui create <name>
To edit this GUI use /gui edit <name>
In the Edit View you can change things like
Click on the Crafting Table to change the Items. You can add new Items by simply Drag&Drop them.
Right Click the Items to change the Item Properties like Displayname and Lore.
If you Right Click the Item you can also add Custom Actions for Left, Shift Left, Middle, Right and Shift Right Click.
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