2x interviews (30 mins each)
Structures, mechanics, environmental engineering, electrical engineering, maths
There are loads of free resources out there to use [see some on this website!]
Do the best you can in all parts of the application process (as they say, every little helps)
Remember this advice isn't official. There is no guarantee it will reflect your experience because university applications can change between years. Check the official Cambridge and Oxford websites for more accurate information on this year's application format and the required tests.
Also, someone else's experience may not reflect your own. Most interviews are more like conversations than tests and like, any conversation, they are quite interactive.
2 academic interviews. I decided to stay overnight as the college offered me free food and accomodation. This took a lot of stress out of the process as there was no danger of being late to my interviews. I was shown to each interview by some students and each was about 30mins long.
Interview 1: Mainly focussed on structures and mechanics. There was a quick question at the beginning about why I wanted to be an engineer then we ploughed on. We mainly looked at the equilibrium of a beam and pulley system. I had no idea what was going on and at one point forgot how to add 10! But they guided me through each question which was rewarding when we reached an answer.
Interview 2: Focussed on environmental engineering, electrical engineering and maths. Drew some graphs. Looked at a couple of circuits and resistor networks (at one point got told that they had never seen someone go about a question how I did). Also discussed the impacts of airport expansions.
Tips: You will be told who your interviewers are.
So you want to be an engineer website is excellent. They should send you a link when you apply.
Engineering website has lots of helpful information about the process.
The student room is full of terrifyingly smart people and all the information should be taken with a pinch of salt but as my school didn't know anything about the application process I found it very helpful.
Cambridge shadowing scheme is excellent and you can apply as an individual if your school is not organised.
There are plenty of really good personal statement books which help you get a good structure for it.
They have now started testing all students for engineering. I was assurred that until the faculty has statistics about the performance of different groups of students and the reliability of the tests that they will not put a huge amount of weight on them.
[Editor's note: this may have been true at the time of writing, but still work as hard as you can for the tests as this may no longer apply]