Hi, for a pca you need to focus on the client rather than offering your opinion. The idea is for them to draw their own conclusion without feeling it has been influenced by someone else.
Use phrases like; how does that make you feel?, and; how would things be ideally in your situation? to find out their thoughts and feelings on what they feel is wrong and to get an idea on what they could do to make the situation better. Reflect back what they have said to you so they can see if you have understood them.
A counsellor empathises with the person so try and put yourself in their shoes and ask appropriate questions to help them elaborate on what they are trying to tell you. Don't use accusing questions like Why? or What for? and if you get stuck for something to say, don't see it as an awkward silence - moments for thought and reflection are important for both parties, and commonplace in a counselling situation.
Hope this helps, and good luck!