You don't go about asking for a Sensei to train you by doing this as all it will lead to is them ignoring you. To get a Sensei(the people with orange names) to train you go to their profile and leave them a vm asking if they have any spots available to train you in the subject you want to be trained in. Some Sensei's will have an Application thread where you can apply for training instead of vm'ing them, and they will usually have the link to their Application threads in their profiles.