I am actively working on documentation for RES 4.0(.1), this wiki still contains articles that are relevant to this version, but small elements (such as screenshots or specific commands) may be out of date. I recommend you still follow the advice in the wiki articles here until the new documentation is released.
Whilst I am working on this new documentation, I have no plans to update the wiki. The new documentation will ultimately supersede this wiki.
From Reddit Enhancement Suite Guide
Reddit Enchancement Suite gives the option of cycling through threads using keyboard shortcuts or Hotkeys. Once a thread on the main page has been highlighted, the following commands become available.
By clicking a thread on any subreddit while Reddit Enchancement Suite is active on your browser, a dotted box will appear around the thread in question. The commands below are then available for use. When a hotkey has been pressed without a thread being highlighted, the first thread on the page will automatically be selected.
|Key pressed||Action on Link||Action in Comments||Shift command|
|.||Show/hide commandline box|
|K||Move up links||Move up comments||Move to top of list Move to previous sibling|
|J||Move down links||Move down comments||Move to bottom of list Move to next sibling|
|P||Move to parent|
|Enter||Follow link||Expand/collapse comments||Open link in new tab|
|X||Toggle expand for image, text and video links||Toggle expand for images in comments||Toggle "view images" button|
|C||View comments for link||View comments in a new tab|
|L||View link and comments in new tabs||View link and comments in new background tabs|
|A||Upvote selected link||Upvote selected comment|
|Z||Downvote selected link||Downvote selected comment|
|S||Save the current link||Save the current link in comments|
|R||Go to subreddit of selected link||Reply to current comment|
|I||Go to inbox||Go to inbox while in comments|
|F||Go to front page||Go to front page while in comments||Go to front page|
|N||Go to next page|
|[||Go to previous image within expanded album||Go to previous image within expanded album|
|]||Go to next image within expanded album||Go to next image within expanded album|
 This command is for links.
 This command is for comments.