If you want to take a gap year but still apply to university at the same as everyone else, then you can defer your entry. To apply for deferred entry is really easy: you just tick a little box on the UCAS application. But before you do that, make sure you check that the courses you're applying for actually accept students who have deferred entry. Some competitive subjects, some universities, and some courses don't like students who have deferred entry. They want students who come straight from school, so there's no gap in their studying. Before you apply for a course and deferred entry, make sure that they are going to accept you.
You're going to need to explain your decision to defer on your personal statement. You’ll need to explain why you decided to take a gap year, and why you decided to defer your entry. If you can't come up with a good reason, or if you can't explain it well enough in your personal statement, then you're going to be in a little bit of a tricky situation. You're going to need to have plans (or at least an idea of plans) in place. You can't just turn up at the interview and say, "I'm going to play computer games for a year." Because, unless you're applying for computer games design, they won’t see the advantage. You have to have a plan; you have to do something productive, something useful, something good with this year.
If you want to defer your entry after you’ve already confirmed your spot, then contact the university directly and see if they will allow you to make the change. If you've applied for deferred entry but then don't want to take that up anymore, this a little bit of a trickier situation, because the university might not have places for you straight away. If they've allocated your place for a year later, there might not be space for you to start this year.
If you want to take a gap year, the advantages of deferring entry are that you're going through the process with all of your friends at the same time. You're applying at the same time, getting offers at the same time, you have the whole experience on results' day and the anxiety about what is going to happen. And when it comes to teachers writing your references, you're much fresher in their minds as opposed to having to remember you a year later. Applying at the same time and deferring entry is going to be a much easier application process.
Your other option is taking a gap year and then applying a year later so you have your grades in hand. Now, you can go through the process with your peers, writing your personal statement, but don't actually apply. Leave your application till September and get it in right when the UCAS applications open. Because you're already applying with your grades, you can pick and choose your universities a little bit better because you know whether you're going to meet the grade requirements or not. And because you've done this, the universities might give you an unconditional offer. You might also have firm plans in place because you've had more time to work out what you're doing on your gap year. When you apply for the UCAS deadline in January, you may not know what you're doing over the summer. But if you leave it for a year and apply when the next round of applications open in September, you might have got your gap year plans already sorted out so you can better answer questions in your personal statement and in an interview as to why you're taking a gap year and what you're going to get out of it.
If you're going to take a gap year, you’ve got two choices: You can apply with everyone else and defer your entry, or you can get your results and then apply and take your gap year later, knowing that you’ve got a place waiting for you when you come back. The downside of this is that you might be invited to interview while you’re planning on trekking a rainforest or relaxing on a beach.
Gap years are fantastic, amazing things, but only if you use them properly.