Rose wedding bouquets can become heavy as more and more flowers are added. Be sure your bouquet is secure and won't topple over. Roses can be heavy and can fall forward if you don't take precautions to securely weight your holder.
I rotate the bouquet around so I can see all the spaces that I need to fill with stock flower.
Looking down from the top I can see more openings.
Try to keep the bouquet rounded to keep a good shape.
Now I'm nearly finished flowering in with the stock flower.