I wanted a nice stylish house number to go on my gate post for some time, but couldn't find anything I liked - at least not at a reasonable price, so decided to make one. Here's how I made it, for almost nothing.

Here's what you'll need;

A piece of slate
Stone sealant
Gloss paint
Small paint brush
Drill
Craft knife

Step 1: Find Some Slate

The key to a nice slate house number is finding a nice piece of slate. I found mine at the bottom of some slate cliffs by the sea in North Devon. Slate had been tumbling down, and there was a huge variety of shapes and sizes. I went for a piece about 1cm thick - you don't want it too thick, or it's too heavy and harder to drill through. You also don't want it too thin, or it is in danger of cracking. Slate is incredibly strong in compression, but it's quite fragile if you bend it, so take care with it.

Pick a piece that is the right size and shape already if possible. You can cut the slate, but it will look much more modern with straight cut edges, which isn't the look I was going for. Chipping away at the edges to get a natural look is pretty risky too, so find a piece where nature has done the work for you already. Pick a piece that's the right shape for your house number. If you live at number 8 you are going to need a round shape, but if you live at number 10245 you are going to need something more rectangular or oblong.

Obviously make sure you have permission to take the slate - many beauty spots forbid you from removing anything at all, so check first. If in doubt, move on to somewhere else.

Once I got the slate, I drilled a couple of holes in the sides for screwing the slate to the wall. You don't have to mount it like this - you can use a strong adhesive for example (e.g. No More Nails), which can also look nice because then you don't see any fastenings, but it is more permanent.

Step 2: Mark Out Your Number

Next get on your computer, and use a word processing package to print out your house number. Go through the different fonts on your computer, or find a new open source one at Google Fonts. When picking a font, don't go for anything too fussy, because you're going to have to paint it. Any sharp points or small details are going to make your job much harder.

After you've picked a font, adjust the text to be the right size for your piece of slate and print it out. Cut out the paper at least 1cm round the number so that you can put it on the slate to check it looks good. If you have the size wrong, just try again. Once you have the right sized text, stick it on to the slate using sticky tape in exactly the position that you want the numbers.

Once you have the numbers in the right position, take a craft knife with a sharp point, and cut through the numbers, scoring the slate. Start from the inside of any numbers and work out. In my example with the zero I start with the middle, because if I had started with the outside of the zero, the inside would have been removed and I wouldn't have been able to cut it in place.

The goal is to mark the numbers on the slate as you cut, so make sure you press down. It doesn't need to be deep though - just a scratch on the surface, not a deep groove. As long as you can see it up close, it's great.

Step 3: Paint the Number

Now that you have finished cutting and scoring, it's time to seal the stone. That prevents it from getting stained in future, and will help the paint to take to the stone. I used some StainStop that I had left over from a tiling job. Check on yours for how many coats and time to dry - I did 2 coats on mine, and left it for a week to dry. It looks shiny in the picture, but that's because it's wet. Don't worry - when it's dry, it will look just like it did to start with again.

Once the primer is dry, it's time to paint the number on. I used some regular outdoor gloss paint. It was meant for wood, but it works great on stone too. I got a small art paintbrush, and simply painted inside the score marks. Take your time - this is the most important step. I'm no artist, but this is just colouring in - anyone can do it.

I needed three coats of paint in total. The picture here shows the result after the second coat - it still looks thin in places at this stage. Your results will vary depending on the stone and the paint, but give it as many coats as you think it needs to look good.

Step 4: Mount It

The final and most scary step is mounting this to the wall. I screwed it to my gate post, which is made of very uneven stone. Bear in mind that slate will snap if you put too much pressure on it, so don't over-tighten the screws. A rubber washer can help the slate to stay snug while minimizing the risk of it moving.

Finally, order a pizza and see how much faster it comes now the delivery guy can find your house.