Up to you if you have a cake, I reckon. But make life easy on yourself - if you don't cook/bake and are likely to worry about it, make life easier for yourself and order a cake made for you (albeit it may cost a few $$) .

I can bake cakes ok but I'm definitely not a cake decorator. When my DS was christened last year, I made a round white choc mudcake, iced it with white ganache (white choc/cream melted together) and kept the decorations simple. I just went to the nearest cake decorating shop and asked the man behind the counter what I should put on a christening cake. He was fantastic in helping me put it all together - and it wasn't that expensive (less than a specially purchased cake, anyway).

In the end, I had a ribbon round the cake and on top I had a cross, some pale blue icing booties, my son's first name and date in bought lettering (not icing), and a couple of other little things to give the cake a lift (icing hearts on wire/tiny icing flowers).

For me the important thing was that the cake represented DS's baptism - that's why the cross, his name and the date. Most cake shops would be used to making/decorating Christening cakes so I'm sure they'd help you re: what to put on it if you buy one.

Good luck with it - it's a special day.

Andie