Getting a new lawn level

[d000hg]

I have a 5x5m former shrubbery I'm turning into a nice formal lawn in front of my house. It's got a slight but noticeable slope and I'd like to build it up to be level, with sleepers or dry stone walling retaining it.

Is there a standard way to ensure it is level? I'm picturing pegs and string but not quite sure how to do this, other than clumsily trying to rest a spirit level on a string which seems error prone.

One corner is at the desired level, the opposite corner is perhaps a foot low. I feel there must be an easy way to do this but I can't figure it out!

 

[blup]

Find your desired level, peg it out, then use a laser or series of straight edges to establish the other levels, and peg them out.

It's not a foundation so you'll have some leeway.

Cheers,

Blup​

 

[Halitosis]

I researched this a few years ago when I re-did my garden, and the best suggestion I found was to first ensure the soil is stone free (a shopping basket makes a great sieve), similarly compacted across the whole area (settlement will otherwise leave peaks and dips), and then the best way to level it is to attach a rope to each end of a wooden pallet or ladder, weigh it down, and then drag it up, down, back & forth, around and around repeatedly. My biggest regret 3 years later is not having done that enough. Good luck

 

[d000hg]

Find your desired level, peg it out, then use a laser or series of straight edges to establish the other levels, and peg them out.

It's not a foundation so you'll have some leeway.

Cheers,

Blup​

It's kind of what I imagined but with it being so low to the ground I'm wondering about the practicalities. If it was higher up I could look along a sightline using a laser level but here, the lowest corner is only maybe 9" below the higher - I feel I'm going to be lying with my cheek on the ground to read any instrument which could get awkward.
I had thought putting a spirit level on top of taut string would be very error-prone but if I can find a long enough rigid edge (cane, whatever) this seems like it would let me establish the level.

 

[Mike10]

Are you planning to play billiards on it?
To level the soil just bang in the first peg to set your level then get a straight piece of timber and use a level to set the next peg at the end of the timber, continue the process until you reach the other side. (If you're not sure how straight the timber is turn it over and take an average).
It is not a large area you could probably level as you go by just placing a plank on the ground with the level on top.
Alternatively use a laser. You don't have to use the laser exactly at the required level, you just need a datum. (setup the laser at one end and measure how far from the line to your desired level, then go to the other end and measure down the same distance.) No need for laying with your cheek on the ground.
If you really want to use a bit of string you can get levels that hang from the line.
Hang the level at the centre of the string so it negates any sag in the line. https://www.amazon.co.uk/Stanley-0-42-287-Line-Level/dp/B001BH4KRU