Shaping up with your favorite herbs
Most good things take time. But few are as simple as herb topiaries, nor taste as good! You'll need a pot, a stake or a topiary form, and one of a few herbs. For standards, lavender, bay (Lauris nobilis) and rosemary are good because of their woody stems. If you want a form such as a globe or a wreath, you can use rosemary also, or myrtle, trailing thyme, or santolina.
If you start with a woody plant, make a standard (the typical "lollipop" shape). Stick a stake in the pot, right in the middle of the plant. Nip off the top growth stem, so the plant will push out all that energy to the side. Trim all stems off below where you want the ball shape to develop. Use your fingernails or a sharp pair of clippers. The idea is not to injure the stem.
For soft-stemmed herbs, you will need both a form and something to keep the stems tied to the form. Green-colored garden ties or raffia will work. Just wind the stems around and around the form. As the plant grows, continue to wind stems around. Eventually, the whole form will fill up. Then you can pinch off ends to encourage bushy growth.
Prune judiciously for about six months, keep the plant on the dry side, and rotate it so that it gets sun on all sides. With this amount of care, you'll get something that looks like you've hired an English gardener.