Terence Blacker: Exclusive: secrets of the stars' Valentine cards revealed

We are approaching a difficult weekend of decision for lovers and would-be lovers. The trickiest date in the romantic calendar, the moment when erotic opportunity and disaster are finely balanced, is almost upon us.

What to say on your St Valentine's card? Passion is important but too much of it, throbbing away inappropriately on a naff Hallmark card, can be alarming. Jokes are fine, but what if the target fails to get it or, worse, gets it but doesn't laugh? There are few things more ruinous to a new relationship than humour incompatibility.

Etiquette guides, always useless when they are most needed, have nothing constructive to say about St Valentine's Day. Fortunately, though, a few people in public life have been prepared to give this column a preview of what they will be sending this year. Some useful lessons on what to do and what to avoid are there to be learnt:

1 Try at least to be slightly romantic. Colette, the wife of the Tory MP Derek Conway, who employs her and (in a virtual capacity) has employed their two sons in his parliamentary office, took an approach which some might find rather too pragmatic:

I bought a card during working hours

For my husband, the famous MP

That'll be £560

Excluding VAT

2 Turning to another politician, we discover that it helps to be personal in one's approach. David Cameron's St Valentine's card is admittedly addressed to every voter in the country but still it somehow lacks conviction:

Roses are red

(No, maybe that should be green, everyone likes green at the moment, sustainable and all that, yes, let's go with green)

Violets are blue

(or any other colour that you like your violets to be, we're totally inclusive when it comes to colour)

If you vote for me

(or any of my colleagues, they're all really great)

I'll love you

(or like, or respect, or have a high regard for you, if you're more comfortable with that)

3 Some people like to quote the poetry of Elizabeth Barrett, Browning or Keats to give their message a literary flavour.

A better idea, to judge by what Brad Pitt will be sending his beloved Angelina Jolie this 14 February, is to combine the personal with the historical.

Bob Dylan says:

Farewell Angelina

The sky is on fire

And I must go

Ian Dury almost says:

There was Angelina

In the back of my Cortina

A seasoned-up hyena

Could not have been more obscener

Brad Pitt says:

Ain't you glad

To be had

By Brad?

4 Most lovers will prefer to express their own particular character in their poems. Here is what Russell Brand will be sending to virtually anyone who is up for it.

You've seen my bookie-wookie

My pervy pixie face

How about some nookie-wookie

Right now back at my place?

No need for talkie-walkies,

Or witty repartee

'Cos all I really fancy

Is ickle-mickle me

5 Finally there is the vexed question of anonymity. Tradition demands an enigmatic sign-off, but then entirely successful anonymity defeats the object of the exercise. Whatever you decide, try to be consistent, unlike this footballer in his message to the new England coach Fabio Capello.

My Valentine dream

Is to be back in your team

Who am I? Just answer this riddle

You can play me wide

Up and down your right side

But I prefer to be played play up the middle

From Guess Who???

Yours, David Beckham