One of the thing that you can do to build your own portfolio is to photograph a model. As you will probably have a general portfolio so you also need to have a picture with a person. There are aspiring models that also want to build their own portfolio and they need a photographer to take pictures of them. Now there is the trend that if you want to find a model and shoot for free then you can ask in your area. In return are pictures.
You can also look online as there are those who can respond near your area. If you know someone then you can photograph them. But here are some things to keep in mind. If the model release form is applicable in your area, you should use it so you can have the rights for the photos and avoid misunderstanding in the future. Pick also the location for your shooting. You can also send specifics on what her clothing must be. Give specifics so you will be on good terms.
You can also give them some instructions but not vague ones. You can say what part of the body is to be listed or positioned below or above. You can download a guide on what are the pose that your model can strike. If she already knows them and is doing great then it is good. If she heeds them then give it to her professionally and with encouragement or a feedback that is positive.