Go through the herbal tea section at your health food store. Read the lists of ingredients and decide if they sound good to you. Try them at home and think how one or another ingredient, to your taste, is unnecessary, good, better,
essential.
Pare the ingredients down to the most important 3 or 4. You are very likely to find them online but keep something in mind, you may well be able to start with fresh and have better quality. Play with ratios in your tea kettle and while you are enjoying all this
experimenting think of alternative sources for the ingredients. One of those sources might be right outside your backdoor

.
Wishing You the Best of Luck, Steve