Here's the very first blocks i ever laid on concrete. I used a spirit level but only for decorative purposes it seems as it went all out of whack pretty early on. As long as its solid it'll stand ah!...

 Here's the hole im working in, bug down to get some sort of level to work from. The old wall goes on and on deep so it didn't reach the bottom of it, which is good otherwise it might fall on me.

 Another view of the carnage. Notice i did dig footings and fill them with crushed up rocks etc. I poured liquid cement over it all and assumed (wrongly) that its sort of self levelled!

 Wow look a real looking wall! Notice though its very much not level at all in anyway. indeed the top bit is about 8 inches higher than the lower bit of wall.

 So a proper lintel was bought (they are very cheep!) to make it look like i'd meant it to be that way. I put great big bits off wood on top. They are called i'm told "wall plates" and are more usually laid to one side of the wall if you are at all compitant, but i was as ever making it up as i was going along, so i did it and odd way and had them on top.

Gawd it hard work for a lazy person.  Here is the roof sort of on, well the beams in (that's a hundred quids worth of wood!) I then put "noggins" (short bits in between the long bits) in which firmed it up to a surprising extent. Then i nailed most of four sheets of Mason board over it. (almost another hundred quid!) I made up frames to match the windows i had... well in theory anyway they were exactly the size of the windows.