You are in control of your personal statement, but you are not in control of your reference, however you can influence what goes into it and make sure it shows you off in the best possible light.
There are three things an admissions tutor's going to pay attention to your predicted grades, your personal statement, and your reference. You know your predicted grades and you have a lot of influence over these because it's how hard you work. Your personal statement, you write that yourself. But somebody else writes your reference, and this is a critical thing that admissions tutors pay attention to. If they see something, they don't like in your reference, no matter how good your personal statement is, you are going to end up straight in the ‘reject’ pile.
Firstly, give the person writing your reference a lot of notice. This is generally going to be one of your teachers or one of your tutors from school, and teachers are busy people. If you don't give them a lot of notice or if you expect them to write it overnight or in a short period, chances are it's not going to be very good. Make sure you give your teachers a lot of notice so that they have time to get the data they need so that they have time to sit down and do it properly so that they're not rushed.
While one person's probably going to be writing it, they're going to ask for input from all of your subject teachers. Go talk to your subject teachers, especially the subject teacher who teaches the course that you want to study. Explain to them why you love the course, why you want to do it at university, what sort of things you've been doing outside of school that will help you be good at this course at university. Perhaps show them your personal statement, ask for input on your personal statement. This will give your subject teachers lots and lots to write about. They can then pass this on to a tutor who's probably going to be writing it. Then that one person who's writing it can collate all of the information from the other teachers. But if your teachers don't know the stuff that you're putting into your personal statement, it's very hard for them to write it in your reference.
Talk to the person writing your reference, have a sit down with them, show them your personal statement. This may not be one of your subject teachers; it may just be your form tutor or head of year who you may only see infrequently. It might be the head of sixth form or it may be a professional person in school who writes the references, but make sure they know about you. Make sure they know about you outside of school, all the extracurriculars you do, all the skills that you've got from other things, why you have a passion for this subject. The more they know about you, the easier it is going to be for them to write a good reference.
The reference is going to be the right place for the school to discuss any exceptional circumstances that may have had an impact on your performance. Any family issues, any health issues, anything that's affected you which may influence the fact that you might not get the grades that you could've done. Talk to the person who's writing your reference about this.
Chances are you're never going to see your reference, but you do have the right to know if you want to, but most of the time they just submit it and send it off. Teachers don't write bad things in references but sometimes the absence of things it more telling for admissions tutors; we write stuff that we have backed up by evidence. So, the more good evidence you can give us, the more good things we have to write.
And then, lastly, don't hassle your teachers, don't nag them. Teachers, tutors are incredibly busy people. We have a billion things to do, and if we have one student who's hassling and nagging, it doesn't necessarily induce you towards writing that personal statement. We know what the deadlines are, your head of the sixth form is nagging us by email every day, it is on our to-do list.
Make sure you talk to the people involved, make sure you tell them what you're good at, make sure you give them the information to write your reference and then, combining that with your personal statement, hopefully, the admissions tutors will see you for the fantastic person that you are.
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