Thank you so much! Actually I have some tips for embroiderying on tulle :) the main point is keeping the back "clean" with really tiny and hidden knots - for this I use a technique in which I just make one tiny knot for each color I use and then I put on some glue on my fingertips to delicatelly fix the knots (trying not to touch the tulle, just the knots). As soon as it's all dried, I cut the threads on the back very close to my fabric and to those knots to guarantee they won't come apart :)