Research is absolutely key. You need to collect some general figures surrounding the cost of flowers, cakes, decor, food, and go from there.
There are plenty of websites that will tell you what you should put aside to spend on things, but this isn’t necessarily the best thing to listen to. The wedding industry wants you to spend £1000 on flowers, and £1000 on a 5-tier cake adorned with sugar flowers, but this isn’t doable for a lot of people.
This is why it’s better to get in touch with some local suppliers. Wedding fayres are a wonderful place to meet a range of suppliers all under one roof. You can ask them for a price list, or for a quote based on what you think you’ll need. You could ask a local florist for the price of 3 bridesmaids’ bouquets. If you do this at multiple florists in your area, you’ll get an idea of which is the cheapest.
You’d be amazed at the cost of food and drink too; sometimes it can be as expensive as the cost of your venue. This is the point where you want to make certain vague decisions: do you want to spend £5k on a sit down meal, or is a casual buffet more your style? Do you want two meals, or to get married at 4pm and just have one evening buffet?
There are a lot of decisions to make, and you shouldn’t rush them. Think carefully about how you want your day to go, as well as if you can afford it.