Water the mother plant the night before to hydrate all the stem ends. After adequate growth on the main plant, take a cutting, using sharp pruners to remove a tip cutting measuring 3-5 inches with no flowers or buds. Remove any bottom leaves up 1-2 inches. Moisten a half mixture of well draining soil mix. Dip the end of the stem in rooting hormone and poke a tiny hole in the planting mix and plant the stem, then tamp the soil down around it to secure it. Water the plant often to keep the soil consistently moist while it roots. Place the cutting in bright indirect sunlight. After 4-6 weeks, the roots should establish. Acclimate the Nemesia to normal light conditions a few hours a day, starting in the morning light and progressing each day over a two to three-week period. Transplant your new plant baby into rich garden soil in full sun and consistent soil moisture.