This advice is contained in a new booklet that has been sent to teachers in an attempt to attract more applicants from the state sector - obstinately stuck at about half of the total for the past few years.
A recent survey conducted for Oxford and Cambridge by the National Foundation for Educational Research found that state teachers often put pupils off applying to Oxbridge for fear they would not fit in socially. And two out of three thought the interviews put their pupils at a disadvantage.
The booklet, compiled by Rosemary Butcher, the university's new schools' liaison officer, aims to dispel such fears and to stress that Cambridge wants bright students regardless of background.
It also scotches the myth, identified in the NFER survey, that Cambridge is more expensive than other universities. In fact, the cost of living is lower than at many universities, with short terms and low transport costs.
In the introduction Susan Stobbs, director of admissions for the colleges, urges teachers "not to believe all the articles that appear regularly in the press" but to contact the university for advice.
The booklet stresses that potential applicants and teachers are welcome to visit colleges to find out more, either at open days or by arrangement at other times.