I recently started one. Watched the instructions on HGTV.
It's quite simple, start w/ a new young plant or train an old plant. The key is to isolate the straightest stalk you can find and tie it to a stake.

On old plants, remove all other surrounding stalks / branches in order to leave the one isolated stalk. On new young plants there are less competing branches to worry about.

Once tied and staked, trim off all lower leaves up to the point you want to bush out. If you want it to be taller before bushing out, trim off all leaves except the top new growth. Once your height is established, trim all lower growth and form into a standard.

Hope this info is useful. I've just started my standard approx 3 weeks ago and it's coming along fine.
Paul

That is a good suggestion above. Rosemary can be trained with very satisfying results and it responds well to trimming and pruning. Since yours is a larger plant I hope that you find that it has a reasonable size main trunk already. I would not be discouraged if the main trunk has already firmed and is not straight like a telephone pole. Some curves to the trunk could prove to be very interesting. I trained a Ficus trunk to curve like appearance and I am thinking of trying it with Rosemary also.

I keep an eye on all side branches and never let them get very large incase I do not want to keep then later. These large branches form unsightly scars which will detract from any good specimen.

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