To keep your flowers perfectly placed, make a lattice pattern out of tape across the top of the vase. Poke the stems through the grid. Remember to trim any leaves from the portion of the stem that will be immersed in water. The water will stay much cleaner and clearer.
I love the simplicity and that it's just so pretty tied with a navy polka dot ribbon! I'll fill a few other jars and tie them with red ribbons to be festive.
A hint: if you often tie ribbons around your vases like I love to do, keep the ribbons in an envelope tucked in that vase when you're not using it. It'll save you the hassle of guessing which ribbon fits which vase and will also save you from continuously cutting new pieces of ribbon.