But stop and think for a moment. Is everything going to match? Whilst we don't want everything exactly the same colour, we want tones coming together; remember that there are different sides to every colour. Your purple bridesmaids may be the red side of purple, but the chair cover sashes you have ordered are the blue side and will actually clash on the day.
Slow down a bit, use suppliers that will work backwards with you. Make you look at the whole picture of the whole day. It's your wedding; it's not your wedding favours are from here, your invites from here and the chair covers are here; it's a day, it's your wedding day.
So you've already bought the wedding favours, because you couldn't resist. Let's start from there. Let's put that wedding favour on the white tablecloth, with a white napkin, glassware and cutlery. Now let's add a ribbon round the napkin, that complements the wedding favour. Now let's add a place name tag to that ribbon. Ooooo let's use that lovely plum card as a backing because it complements the wedding favour box and the napkin ribbon - and suddenly your wedding stationery "look and design" starts coming together.
Don't be frightened to say to your suppliers "how will that flow with everything else?". A good wedding supplier will walk you through it - we do it every day, hopefully you will only do this once and we only get one day to make it work.
At the end of the day, it will also save you money - stop buying lots of bits on e**y and hope for the best .... look at your day as a whole and it will come together.