On Open Diary, a “Friend” is somebody who you can share Friends-Only entries with, and who will appear on your Friends list so you can see their latest entries.
To add somebody as a Friend, look for a circle with a plus sign next to their name:
If you click the plus sign, this will send a Friend Request to that person. In order to become Friends with that person, the other person must accept the Friend Request.
Once you have sent a Friend Request, you will see a minus sign in a circle next to the person’s name – if you want to cancel the Friend Request, you can click the minus sign to do so. This will only work until the other person accepts your Friend request – after that, you will have to remove that Friend to take the person off your Friends list.