Depending on your arrival day and your program, you will have a registration meeting either the first or the last week of August. On the registration day, you will be given a T-number (student number), an access card and a PIN code for the card. You will need the card to access several facilities on campus, so please bring your card with you.
After you have access to the KTH website, you should update your temporary address. This is the address to which all KTH mail will be sent, including your student ID card.
Most professors will provide lecture material either on KTH social or on Bilda. I suggest you start practicing with those. On Bilda you will also have the SWELL online Swedish course. You can find it under Events > Catalogue.
You should have received detailed information about your registration via email, and you can ask your coordinator for more information about your program.