Their body and clothes are both parts of what they are. Keep your descriptions clear and original. In this way you are examining the person in the same way Hughes considered his jaguar. When you are finished at the zoo or the high street, come back and look over what you have. If so, work at it gently, letting it take its time.
Some poems are five minutes in the making, others five years.
Tomorrow you may find you want to write another one, and the day after that. It may even come to seem like second nature. In the next workshop I'll take a look at the next stage - when you show someone else your work. A few pointers on seeking and dealing with advice.