elderflower--do you have a walking foot? I find using one helps with napped fabric or thick fabric...also, you could sew through tissue paper as well...I use fabric glue for the seams to tack them down...just a dab and it seems to hold quite well.
Thanks for the tips alwaysinmyroom. I don't have a walking foot. In fact I never heard of them until recently. But I just joined a class to learn how to make patchwork quilts and it seems I need to get one for that. Great that I can use it for velvet too. I do use tissue paper for slippery satins and similar.