Choose the appropriate time of year to cut the plant. Plumeria plants bloom between March and November. Make your first prune right before the season begins. If you cut the plant during months it is not actively growing and blooming, the cut area will be prone to drying out over time. Pests will burrow in the open shaft of the plant and lay their eggs -- hatching right along with the new season of blooming flowers and destroying your plant.
Consider the size of your plant. If you have a potted plant, the branches should grow no larger that twice the height of your pot. This is done to avoid branches becoming heavy enough to bend or break when blooms arrive. Cut your plant during its blooming season as the stems grow, so that it will not outgrow the pot. You may need to cut as much as 4 to 6 inches off the stalks, if you have let the plant grow too long. But don't worry. During blooming season, the flowers will return quickly.
Hold one stem at a time, and observe the node area. This is where leaves or branches meet with the stem. Be careful not to pull the stem and risk up-rooting it. Instead, gently separate it from other stem bunches, and move it to where you can gain a clear angle as you prepare for the cut.
Cut the branch with a sharp knife or pruning tool. Maintain a 45-degree angle as you make the cut. This angle allows moisture to flow into the core of the stem. Never randomly slice or tear at the branch.
Manage the plant's blossoms over the season by cutting no more than half of the stems at one time. This will allow you to rotate pruning in a way that will allow active blooms throughout the season.