Ask for referrals and recommendations and do your own research to get estimates for cake costs.
If possible, sample a piece of cake, so that you can ensure you have a great-tasting as well as a great-looking cake!
You should book your cake designer at least 6 months before the wedding.
Make an appointment to see the cake designer(s) and when you arrive, ask to see his/her portfolio of work
Get testimonials or contact information of past customers
If satisfied, discuss the design options with the cake designer. Be sure to tell him/her about your wedding colours and theme and whether your reception will be indoor or outdoor. This often determines the type of icing used (e.g. a cake iced with buttercream may be unsuitable for an outdoor wedding, since it may melt and drip)
Ask about possible hidden costs such as transportation to wedding site, assembly at wedding site, dismounting etc.
Enquire about how much deposit is required and when it should be paid, as well as when the balance is due.
Once you book your cake designer, get all the specifics in writing (cost, size of cake, number of layers, colour & type of icing, delivery date). In other words get an invoice from the cake designer.
Once you pay a deposit, ensure that you get a receipt