hiya.
1) copy the link for your journal as you have done previously.
2) go to edit your signature
3) Where you want the link to be displayed write the words you want on show for eg ' SW's pregnancy journal'
4) Highlight the text you have just written
5) Can you see where the font options are? the B I U etc. You should be able to see a globe in that line with a little chain to the bottom of it, thats insert link, click.
6) This should bring up a little pop up box that requires you to insert the link to your journal you previously copied, paste that in and click okay.
7) In your signature now the title you wrote should be clickable to your journal.
Hope that makes sense!