DIY can sometimes seem a bit daunting for even the most competent of people, but it doesn't have to be. We've put together a little guide to take you through the steps of fitting a new door so you can see how straightforward it is. Obviously, the first thing you need to work out is what kind of door you need - internal or external, flush (smooth) or panel, lightweight or fire check. As a rule, your sturdiest doors should be for your kitchen and front doors.

Once you've decided what type of door you need, then buy one as close to the size you need as you can. Retailers sell the most common door sizes so you may be good to go with an off-the-shelf model, but often a bit of measuring and trimming is required. Measure the frame length and width, then mark these on your new door. Allow for 5mm clearance at the bottom and 3mm on the other sides. Then, remove the existing door from the frame ready for the new one.

Once you've got your measurements marked, it's time to trim off the excess. Small amounts of spare wood (as a rule, less than 5mm) can be removed used an electric or hand planer to ensure you don't take off too much. For anything more than that use a circular saw, but make sure you don't cut off more than 15mm from any edge or it will weaken the door. In this case, you should investigate buying a different size instead. Also, keep your trimmings equal so it stays even.

Next, you need to double check that you've trimmed off the right amount and that the door fits into the frame. Slot it into the space and wedge it at the bottom so you get a good idea of the fit. If you're changing your hinges, then you should do this once you've checked the fit of the door. Make sure the hinges fit into the recesses in the door frame then wedge the door back into place.

While the door is wedged, pencil the hinge positions onto the door edge. Then move the door so you can chisel out the waste wood so that, when you put the door back into the frame, the hinges are flush with the edge of the door. Make holes in the door with a 3mm wood bit so you can screw in the hinges, hold the door in the frame and screw in a couple of the hinges. Check the door opens and closes, then screw in the rest.