Event styling and design is comparable to interior design or fashion and works very much with ever changing trends and seasons.  For this reason my advice would be wait until the current season 9-12 months prior to your wedding before locking in your chosen style, this way you won’t confuse yourself with ever changing designs.
Once you have finally defined the style you love then ‘stick to it’ this will assist you to follow through the theme in every detail of the wedding with clear direction from the outset, the shopping experience will be much more fun!  Having all aspects of the wedding working cohesively will give you a polished look and options to play around compiling your images after the wedding with no mismatches.
Make sure all final details are confirmed with your venue and suppliers 4 weeks leading up to the wedding date this will allow your team plenty of time to execute their service well, leaving you with a stress free lead up to the wedding enjoying the moment!