When you post a trade, and it is completed, that is when the Bench Points are awarded. When you go into your Trade Manager and mark it as received, you also have the opportunity to rate the trade in the 4 categories. You can rate the other trader, and the other trader rates you. These scores are as important as the Bench Points, as they give an indication of what kind of trader you are, based upon past experiences from other traders.
These are all discussed in the FAQ, so it would be good if you took a few minutes and read thru them. Please do not hesitate to ask anyone if you have any questions. We have a great group of MODS and an even better community of knowledgable traders here. Everyone is always ready to help.