1. why you want to go into Marketing?
2. what made you aware of Marketing in the first place?
3. what made you interested in Marketing?
There is also an (in my opinion) unfortunate tendency to make personal statements read more like short stories or film scripts in the US at least. I think there is going to be some difference (perhaps significant) in the way UCAS personal statements are written. The UCAS personal statements want to see things like
1. why are you suitable for the particular university/ program of study
2. what relevant experience and expertise do you have
3. which clubs or societies did you join (and which hopefully demonstrate your commitment to the field of study you intend to pursue)
Here's a helpful link.
Sunil recommends the following next steps:
What makes you want to study marketing, do you have any experiences that led to you making this decision e.g. if your school did any enterprise challenges did you enjoy the marketing role?
If you study Business Studies at A-Level or GCSE, which aspects of that have made you want to pursue marketing?
Take a look at some of the prospectuses for the courses you might be interested in. Are there any focus areas you could pull out that appear frequently across the different unis you're interested in e.g. you're interested in the psychological aspect of customer behaviour, you love expressing creativity, you want to learn more about xyz.
Are you willing to consider that you are asking the question the wrong way round? If so, start from your talents--what do you and/or others admire about your knowledge and skills?--and work towards your goal. What do your present talents potentially contribute to being a marketer? What skills/knowledge do you lack and how might you fill those gaps?
It would be useful if you had some idea about what you would like to market. Property? Technology start-up companies? Mineral futures? Antiques? The more specific you can be about this, the more specifically you can evaluate your present resources and the resources you will need to acquire.
By performing this kind of evaluation you will have a clear picture of 1) your goals; 2) your current assets; 3) the steps you might take to fill the gaps between 1) and 2).