To manage your SSH keys, simply visit the "SSH Keys" link from the top menu.
If you currently have no SSH Keys on file, you will be presented with a box to "Add A New SSH Key".
If you do have some SSH Keys on file, these will be shown in a list above the "Add A New SSH Key" box.
Enter a name / label for the key so you can identify it later (e.g. Work Laptop, My iMac etc...) and then paste the key into the SSH Key box.
Your SSH Key should look similar to this
Once entered, click "Add SSH Key". If successful, your SSH Key will be added to a list above the "Add A New SSH Key" box, the fingerprint of the key so you can confirm it's integrity and the date it was added to ServerAuth will also be shown.
If your user has been granted access to any servers, your SSH Key will automatically be added to the server next time it syncs.
Visit the "SSH Keys" link from the top menu.
Find the SSH key with the correct label that you wish to delete. If you have a copy of it and it's fingerprint, you can even check that too to make sure you have the correct key.
Once found, simply click the "Delete" button to the right of the row. Then click "Ok" to confirm the deletion.
If your user has been granted access to any servers, your key will be automatically removed next time it syncs.