Each lesson is typically 60-90 minutes long, depending on schedule and level, and is conducted over the Internet.
I may also recommend my favourite textbooks or CDs. which I use as a basis for some courses; for these, I can provide Amazon links. or supply them to you directly. Homework is set at the end of each session, emailed by the student once completed, and discussed in the following lesson. The speed of progression is entirely determined by you!
If you wish to take exams, then these can also be booked for you.