The intended way to take these tablets is sublingual: put one tablet under your tongue and let it dissolve slowly instead of chewing or swallowing it whole. The oral mucosa absorbs glycine directly, so the amino acid does not need to pass through the whole digestive tract first. Since the tablet is meant to stay in your mouth for a few minutes, the cherry flavour is not decoration — it makes the sublingual process more comfortable.
The "Forte" version usually contains a higher amount of glycine per tablet than ordinary formulas. That means you should check the per-tablet amount on the label and follow the serving size stated there rather than assume you need several tablets. It is fine to take it at different points of the day depending on your routine. Many people choose it before a mentally demanding task, in the evening when they want to wind down, or after long drives and when sleep quality drops. It does not need to be taken with food, but taking it at roughly the same time on the days you use it can help you remember it.
Store the tablets in the original blister, in a dry place out of direct sunlight, and keep them out of reach of children. This product is a food supplement, not a medicine, and is not intended to diagnose, treat or prevent any disease.