Make sure that declarations of love and lamentations of your significant others' absence are communicated solely via wallposts. Facebook's ‘inbox' is a completely gratuitous feature, and is to be ignored – Zuckerberg was being ironic
Adding extra vowels to certain words has the effect of conveying a heightened sense of longing – anything you say will have twice the effect. Compare a simple ‘I miss you' to an ‘I miss youuuuuuuuuuu'. But employ discretion, and do this sparingly — you don't want people to think you're being insincere
Ensure that your profile picture is regularly, if not always, of you and your partner. Your profile picture should highlight not just your love, but also the ‘passion' of your relationship — show everybody just how crazy in love you are. This can be achieved by staging pictures of you and your partner gazing into each others eyes, holding hands, or just laughing at a private joke (exotic locations also make for excellent backgrounds)
If you're in a long-distance relationship, and don't have a recent-enough photograph, it is wise to search for a stick and then locate an area of sand (or snow — depending on your location). Inscribe your partner's name upon your chosen surface (hearts and exes are optional, but highly advisable) and voila! You know what to do next
If you chance upon a quote or lyric that aptly describes the nature of your love, never hesitate to insert it as a caption in a picture or post it as a status update — this is a succinct and effective way of telling everyone how you feel
But most importantly, just have fun! There are many creative and exciting ways to show your love on Facebook, so stop kissing and get clicking!