You will need to register with UCAS, (the universities and colleges admissions service) during the autumn of Year 2013, usually through your school or college. Your teachers will be able to support you through the process.
Applications are made online and can be completed in stages. The most important part of your application is your personal statement. The main deadline for applications is January 2015.
Most applicants should receive all offers or rejections by the end of March. You must accept or decline any offers by the date specified by UCAS (May 8th if all your choices replied by the end of March).
You should apply for your student finance as soon as you have received and accepted your offer. If the university offers scholarships or bursaries, you may also need to apply for these now.
The deadline for applications made through "Adjustment", the system whereby if you who have met and exceeded your initial offers you can reassess your options and perhaps gain a place on a more competitive course. Clearing applications should be received by mid-September. The final date for making new applications through clearing is mid-October. The final date for prospective students already in the Clearing system to confirm places on courses beginning in that calendar year.