When working on your cake design you should be asking yourself these questions:
* how many guests will be attending?
* will you be serving other desserts?
* coffee or dessert portions?
* if it's a wedding cake - is the cake additional or will it be served as dessert?
Coffee vs dessert portions. What does this mean?
You may have heard the terms 'coffee' or 'dessert' portions. These are references to the size of each portion or slice of cake that will be served to your guests. As a general rule:
Coffee portions are around 2.5cm x 2.5cm x 10cm (or 1" x 1" x 4"). That may sound like a small slice to you but you have to remember that these cakes are usually very decadent and luxurious and served after a 2 or 3 course meal or lots of canapes! This is the traditional portion for wedding cakes.
Dessert portions are a little bigger and are around 2.5cm x 5cm x 10cm (or 1" x 2" x 4"). These portions are typically used when there are no other desserts on offer. You should bear in mind that if you opt for dessert portions you will need double the amount of cake!
Serving other desserts?
If you will be serving other desserts you may be able to get away with a smaller sized cake because there will be other baked goodies and sweet treats on offer. For example, you may opt for a single tier rather than a 2 tier cake.
* The number of portions also depends on whether the cake is a round or square cake - a square cake will yield more slices.
* Is the cake cut by a professional or novice? Wedding venues are experts are maximising the number of slices where your friend or relative may not be. This can impact on the number of portions.
* 'Stanard' sizing - many cake decorators have 'standard' sizing for their pricing and each cake decorator may have a different 'standard'. A standard cake may be 6 inches, 7 inches or even 8 inches. It's always best to ask so can factor this into your design and budget.

Image credits: Pinterest: Linda Lomelino, Nouba and We are Scout