A wedding trial is primarily for the bride, the purpose of it is so that you are able to hone in on the look that you have been hoping for and adapting it to suit yourself and perfect it.
I am often asked if it is necessary for any others in the bridal party to also book in a wedding trial ahead of the big day itself. The short answer is that it should not really be necessary as long as they come with images of what they want to achieve on the day. When I make an exception to this, is if there is something of particular concern to an individual in the bridal party and that having a wedding trial will iron out this worry.
Whether you have a wedding trial or not, your wedding hair and makeup artist should be able to interpret the look that you want and the best way to succeed is to have clear images and ideas of what you are after.