Dig out the hole 6 inches 15cm wider than the outside side of the pillar you want to build. It should be 2 to 3 feet/ 60cm to 100cm deep depending on how soft your ground is – the softer the ground the deeper you’ll need to go to hit hard ground.
If your pillar is going to have any services/electricity you can build in a piece of plastic pipe into the middle of the pillar before filling it with concrete.
Depth of concrete
Hammer in iron rods to a depth of 1 – 2 feet 30 – 60 cm depending on how much concrete you want to pour in for your foundations. Put in at least two rods at either side of the foundation and put a spirit level across – this will let you know when enough concrete has been poured and it will be level.
Pour the concrete.
Begin building blocks
After two to three days you can begin laying blocks for your pillars.
Lay a string line across the front of your entrance so the front side of both pillars are in line with each other.
Keep your pillars square
Lay the two front rows of blocks along this line first and then use a square inside to make sure your pillar is square.
Keep building up until you get your desired height keeping your pillars square and plumb.
Coping on top
Finish with the coping of your choice
Then finish plaster and add your electric services.