When you are making a flower arrangement, a good way to start is choosing a colour shade to function as a base for the entire arrangement. Here, different white flowers have been chosen, such as limonium, ranunculus, and freesias.
Then add flowers to match the other colours of the table arrangement. Here, a few light purple freesias have been added to match the purple candles of the table as well as a single light rose anthurium.
Vary the height of the flowers for a dynamic look and a bit of wildness. And make sure the arrangement looks nice from all sides. Simply continue to turn the bowl as you are working on the arrangement to be able to look at it from all sides.
Remember to soak the floral foam in water. Both to make it more stable but also to avoid having the flowers wither if you are using fresh cut flowers. This is especially important if you are making the arrangement beforehand and not on the day of the event.