Tips to help you pass your MOT

Firstly - Turn up on time for your MOT appointment - the last thing you want is to keep the MOT tester waiting. This is a sure way of how to upset him/her straight away. Also if your vehicle is excessively dirty and/or muddy, clean the dirt from the wheel arches & suspension components, as all these areas are part of the MOT test
Check your windscreen washer reservoir - ensure you have sufficient washer fluid to clear the windscreen. You can fail the MOT if there is insufficient washer fluid, which when applied to the windscreen does not effectively clear the windscreen.
Check ALL exterior lights are working including the Number Plate bulbs. If you need to change the headlight bulbs, ensure the bulb is fitted correctly. Incorrectly fitted bulbs (and yes they can be fitted & work upside down!) cause the headlamp aim to be incorrect. Bulbs not working & incorrect headlight aims are both MOT failure items.
Most indicator bulbs are white bulbs which have been painted 'orange'. The paint over a period of time peels away due to heat. Should the indicator bulbs show 'white light' with a hint of orange - replace them, as this is another MOT failure item.
Tyres - the minimum MOT wear limit on tyre tread is 1.6mm across the central three quarters of the tread width. However should any of the tyres have bulges, cords showing, cuts in the tyre wall or signs the tyre is perishing, get them replaced prior to the MOT. Check all tyres are of the same size across the axle & fitted the correct way round! The rotation of the tyre is just as important. Look at the inside wall of the tyre, this may mean lying on the ground with a torch, but will save you time in the long run.
Wheels - the most common failure with wheels are dented inner rims, mainly caused by potholes. A dented rim will put pressure on the tyre with the possibility of a 'blow out' or loss of tyre pressure. Again replace if necessary.
Windscreen - nearly all vehicles have minor windscreen damage. The best way to check your windscreen is to sit in the driver's seat & trace an imaginary line the width of the steering wheel top to bottom of the screen. Look for any damage i.e., chips, cracks etc. Any damage in this area which is bigger than 10mm (about the size of a 5 pence piece) is an MOT failure. Other than in front of the driver the damage can be up to 40mm. Damage not in the area swept by the wiper blades is not testable.
Horn - if it doesn't work you fail the MOT.
Exhaust System - If you have noticed your vehicle sounding more & more like a 'tank' or the 'boy racer' from next door or possibly a 'knocking' sound from underneath when driving over rough or uneven ground check your exhaust. Broken exhaust hangers/mountings & a corroded blowing exhaust will fail the MOT.
General Vehicle Condition - if you have encountered the wrath of the 'shopping trolley or parking bay bollard' & have lost a wing mirror or damaged a body part, leaving a sharp or protruding edge, you will fail the MOT. Either completely remove or replace the part or apply tape to the damaged area as a temporary repair.
Registration Plates - if any of the digits are obscured on either front or rear plate due to damage or water ingress. Replace the plates as this is an MOT failure. Also correctly spaced letters and digits are mow a must!
Seatbelts - check all the seatbelts webbing/strap to ensure they are not damaged or frayed. Dogs love to chew these items but they are an important safety item & damaged parts will fail an MOT.
Ensure the Boot & Back Seats are clear (apart from fitted child safety seats) to ensure they can be inspected. It is rumoured as from 2012 the spare wheel will be an MOT test item & access will be required.