Nothing gets you motivated like music. Having a super upbeat playlist can improve your mood and help to keep you in a rhythm.
There will be marker points along the way that let you know when you've run 5km, 10km and when there's only 1km left to go, and they are hugely encouraging. But you may find it helpful to also use an app that measures your progress, such as Map my Run or Strava. It can feel like an age has past between some of the marker points, especially when the going gets tough, and that mental countdown might help to keep you going.
For the first few kilometres you can start to think 'whatever made me imagine this was going to be a good idea?' but once you get to the 10km mark you can really hit your stride. Your body will pretty much keep ticking along; it's the brain that may tell you to stop. Visualise the sense of achievement you'll feel at the end and use that to spur you on.
Don't be alarmed at the number of lycra-clad super-athletic types that speed past you at the start. You're highly unlikely to comein in last. It's best to run the first few kilometres slightly slower than normally, then speed up in the second half. Your limbs will thank you for it later.
By the 17km mark your body will be tired and this is the point where you can really start to flag. That's when it's important to keep your mind occupied – count spectators, high five them, take in the scenery – think about anything other than how much your legs feel like they've been stuffed with candy floss.
Okay, this might be a slight lie, but the principle is true. What goes up, must go down (unless you're running a really tough half marathon up a mountain and, well, that's just madness) - knowing there's a nice downhill run the other side of an uphill section can keep you going and gives you a chance to get your energy levels up again.
It can be really helpful to talk to yourself nicely - think of it as encouraging your inner child. Say things to yourself like 'keep going, you're doing really well (insert your name here, it really helps to say your name), only 2km to go, in 20 minutes this will all be over, you've got this, yes, you're doing it'. It really, really helps.
As clichéd as it sounds, it's important to set your own goal and aim for whatever achievement makes you happy. Whether you push yourself to do it in under two hours, or simply aim to finish it – it's your race to run however you like and the sense of achievement at the end is amazing.