Wow, a lot of really negative comments about Make up Artists here! I feel the need to stand up for my profession. There are hundreds of thousands of make up artists, some fantastically good ones and some bloody awful ones.
The same way you would shop for your wedding dress, or anything else for your wedding, you should research what/who you are paying for and not take pot luck. And definitely have a trial beforehand. Would you choose a wedding dress off a photo on a website and then open the package on your wedding morning, having not ever tried it on, and just hope it fits and suits you?
Even the very best of us are not mind readers, so if you do get your make up done on the day, having never met or had any form of chat or consultation with the artist it's not a big surprise to end up with something you didn't quite have in mind. Many things are open to interpretation and not everyone's interpretation is the same. For example, someone may ask for a "natural" lip colour and where I would read this as something close to the colour of their lips, they may mean beige. If you were to tell a wedding dressmaker you want something long and flowing the chances are you may both have a completely different image in your minds.
Getting a Make up Artist to do your make up will not mean you get an orange face, or look like a clown, or a hooker - unless you get a shit make up artist! If you get a really good make up artist, you are more than likely to look shit hot, for the whole day until you fall into bed. You will have photos of yourself that you keep forever and feel chuffed to bits with.
If an extra £30 (which is incredibly cheap) is too unthinkable for a trial beforehand, think how gutted you would be having not had a trial and then ended up on the day with a look you don't feel good in and feel a pang of regret every time you look at the photo on your mantlepiece?
Most make up artists have a website showing their work. Look through a selection of them and ask yourself if you'd be happy to have the quality of their work on your face. If the answer is no then look at another. It's easy. If you browse in a shop and none of the stuff in there is your cup of tea, you'd go somewhere else after all.
Sorry for my long post but it breaks my heart and poses a big threat to my profession when there is a string of comments on a discussion like this pretty much saying that getting a "professional" to do your make up is going to make you look terrible. There are a lot of "so called" Make up artists out there giving us all a bad name!