Hello!

I was asked to make a wedding cake for a friend - and I have the creative hand to do which ever I'd like.

It will be 3 tiers...
She only wants the top tier to be real - and the other two tiers will be fake.
However, I don't know how I will go about picking the sizes for the two dummies....
They will not be eating the top tier - just cutting it.
It will be a 6" round cake

But I need help picking the sizes for the other two dummies, I just don't want it to look 'off' Is there a rule, or it's really how ever many servings, - thats' the cake size?

Many people would do an 8" round and a 10" round. I personally prefer a 4" difference between each tier, so I would do 10" as the next tier down and 14" as the one below that. It's more a matter of preference - there's no hard and fast rule.

Depending on what look she wants, you could do 6", 8", 10". Or if she wants a more grand look, you could larger like 12", 8", 6". I usually try to keep the size ratio even between the tiers but many don't.

I would do 6" 9" 12" or 6" 10" 14". I like to put big flowers on a cake, so the 4" difference in tiers works best for me.

Ditto to the others. I usually find the 2" differences between tiers to not look or feel right when I've done them. I stick to 4" increases between tiers so if the top were 6" then I'd do 10" and 14" dummies.

It's all really about personal preference and overall design though.

I think it depends on how tall your tiers will be. If you are doing 3" tall tiers, having a 4" difference between tiers looks short and frumpy to me.

Thanks for all your responses
There will only be flowers on the top tier... and ribbon on the others..
The second tier will have a flower/ribbon in the middle of the cake