Paint a Rainbow Theme - I'm not a fan of the bouquets, or the bridesmaids, but all the rest gets my vote on how to decorate a rainbow wedding.
Une ancienne menuiserie revisitée
DIY washi tape tea lights - probably not this color but an easy way to dress up tea lights or even bigger candles
DIY pompons en tulle pour déco romantique
Tutorial: DIY Tissue Paper Pom-Poms this tutorial is pretty good. Use square sheets or tissue for a rounder Pom Pom. Tie the middle with ribbon and tied several on ribbon and hung them for a backdrop. Use thin tissue paper and fluff gently.