On Dreamwidth, go to My Account Settings. Underneath Crosspost Settings, there's a line labeled "Footer" which says "Add the footer to the post on the other site:" and a drop box. Select "Always" and then scroll down and hit "Save."

Oh I've already got that - rahirah helped me with those directions - what i meant was the link box that shows up on the sidebar of an LJ or DW journal, usually under the profile image or calender where you have links to your other website, blog etc.
Ah, okay. Here on LJ, go to "Journal Style" and then select "Customize your theme". On the side bar, you will see "Links List". Click that and then enter the name of the site you want to list first on the first line next to "10" and then the link to it underneath it. Keep going with the rest of the links you want to add on the subsequent lines.


Edited at 2012-12-19 07:00 pm (UTC)
*nods* I realized that once I followed Gab's how-to directions for LJ, so now I've got it set up on both. (Although what was I thinking setting up two journals when my brain can hardly handle the one? I have no idea.) On this LJ template I'm using (Woodcut) the box is pretty far down the sidebar, but no big.)
Some layouts will let you move the various components around on the page - I'm not familiar with Woodcut in particular, but it's worth poking around that customization pages. :)