A successful event is one with a theme. There are many themes for weddings. Choose one that you feel comfortable with as it will be the main attraction in the hall.
You can get a designer to help you achieve this. Just remember to put it into the budget.
You should a take picture of the venue and measure the space so that you know where you want the tables and the dancing area to be.
Remember to check out what flowers are in season at the time of your wedding and if they coincide with your theme. If you are doing this with a designer they will help you with this decision.
Finalize the flowers at least a month in advance.
Match decorations to color theme for a high quality look.