You just got fresh flowers, lucky!
Let's keep them fresh!
Water
The most important step! Replace with fresh water every other day if you can. Avoid using soft water (kitchen sink is usually the best!).
Temperature
Avoid drastic heat or cold drafts. The blooms will open faster as they warm up.
Pruning
Remove any spent blooms or stems. Trimming the stem ends by 1” will help keep the flowers drinking up the fresh water.
Enjoy watching how the blooms change as they open!