Christening etiquette and gift?

[AlunWynsKnee]

Dc and I are going to a christening. I know nothing about how they work or what sort of gift I should get.
I'm an atheist so wouldn't normally get invited or go but I'm going to this one for reasons that don't matter to the thread. They are church (C of E) attenders, not related to us and in their 20s. We're just guests not godparents obviously!
Is there a 'dress code'?
Does the gift need to be religious like a bible or a St Christopher? Or can it just be something like a toy?
Is there anything else I should know?
I've never been to a big christening so I don't know how it works.

I like steiff bears for christenings.

Noted Sage although I do enjoy a good hymn :)

One of my sons best christening gifts was a wooden Noah's ark...religious but not overly so! He got loads of money boxes so not one of those! Books are a great idea!

I like steiff bears for christenings.

Nice price tag particularly if presents have recently been bought for the baby's birth etc.

One of the last christenings I went to had an expensive john lewis gift list in case they got duplicates or things they didnt want.

Wow, that is tacky AF!

I give a set of Royal Mint coins from the year the child was born or a Premium Bond. Or something personalised like a silver-plated or leather bookmark with their name and perhaps a Biblical quote.