In order to be able to post using different user pictures, you need to make sure that each user picture has a corresponding keyword. While logged in, visit
http://www.livejournal.com/editpics.bml. In the box next to each picture, enter a keyword that you associate with the picture. Each picture can have up to five keywords.
If you wish to credit the creator of a user picture, you may wish to do so in the user picture's comments, not its keywords.
Individual keywords may contain spaces, but should not contain commas. Commas are used to separate keywords if you would like to have more than one keyword for a picture. For example, you may enter "happy" or "friends at mall" if you want only one keyword, or "laughing, smiles, my friends" if you want three keywords. NOTE: You do not need to enter quotation marks around your keywords.
If you change a keyword, all comments and entries using the old keyword will then show your default user picture (or no picture, if you do not have a default selected). This also occurs when you delete a user picture and the keywords associated with it.
To use a different user picture with each entry when using the web update client (
http://www.livejournal.com/update.bml), you must be logged in, then select the user picture from the drop-down menu titled "User Picture Icon." You can also use different user pictures when posting from a local client by setting the correct post options (if supported by the client).
In order to choose a different userpic with each comment, you must be logged in. When commenting, select the user picture from the drop-down menu titled "Picture to use."
If you want your style to display your user pictures alongside your entries on your Recent Entries page, you will need to use keywords to select the images when posting and customize your style.
FURTHER READING
What are user picture comments?
http://www.livejournal.com/support/faqbrowse.bml?faqid=206
How do I delete a user picture I no longer want? What happens when I delete a user picture?
http://www.livejournal.com/support/faqbrowse.bml?faqid=51
Where can I find user pictures? How do I give credit for a user picture?
http://www.livejournal.com/support/faqbrowse.bml?faqid=194
How do I customize the look of my journal or community?
http://www.livejournal.com/support/faqbrowse.bml?faqid=7.
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