If you are from outside the EU/EEA and not a Swiss national then you will need a visa to study here.
Students wishing to study for 6 months or fewer can apply for a student visitor visa. More information can be found from these two sources:
Students intending to study at the college in excess of 6 months will need to apply for a Tier 4 visa. More information can be found on the following site:
Alternatively you can read the visa section in our comprehensive International Student Guide.