As the rain falls here in Kentucky in April, I know that the blooms and beautiful landscapes will follow.
(You may want to lay this all out on a old cutting board or something similar. The pigments can bleed.) Lay out your foundation piece on the surface you plan to hammer on. Then lay out your flowers in a pleasing arrangement. Some flowers will not turn out like you think. Have plenty of pieces to experiment with. They don't all turn out like you think. I even did some on some heavy weigh paper for bookmarks during my experimenting. After laying the flowers, you want to put something over the flowers. Paper towels, another piece of muslin etc. This will sandwich the blooms. Then you start hammering. Don't go crazy but you are basically pounding out the pigments onto your muslin. Hammer the surface until all flowers are smashed. Carefully peel back the layers, trash the old petals, leaves etc. Surprise!! Every piece will be different. Experiment and have fun.
Not sure I'd use this for a bed quilt but makes a cool wall hanging.