laying turf...advice needed!

gardenroute

1. Clear site of debris - sticks, stones etc
2. Start rotovating. If there are stones in the soil, start away from cars, greenhouse, etc.
3. Look across soil for any obvious dips and bumps. Fill in to get roughly level.
4. Rake lawn flat - removing any stones as you go along.
5. Sometimes if you had to move a lot of soil around you have to rotovate again to give an even depth of cultivation across the site. Don't be afraid to go back a step if you want to do a good job.
6. Rake soil into a fine tilth and then walk across whole site on heels to firm the soil.
7. Lightly rake soil again to remove footprints.
8. Lay turf avoiding running joints i.e. stagger the turves like brickwork and press them into each other to prevent any gaps in the turf.
9. Tamp them down with a sledgehammer and a plank of wood.
10. Water, water, water. And don't walk on it until the first cut - i.e. when its started growing.

Some people brush sand over the turf to fill in gaps - but if you do it properly you won't need to do this.
A few bags of compost or sand mixed into the soil will have very little effect across a whole lawn.
If you bring in soil/sand etc, make sure the ground is level first so the imported material is at the same depth across the site. Its only worth importing soil to raise the level, e.g. to bring the lawn up to be level with a concrete path; or if there is not enough top-soil to work with -sub-soil cannot be raked out into a tilth.
Some people apply a base feed to the soil to help the grass take; I can't tell you if this makes a big difference.
If there are stones in the soil, the turf immediately above it will die - they just can't root through stone.
If the turves shrink slightly and you can see gaps between the turf you are not watering it enough.
This is hard work; especially when you first start raking out - help is always welcome.
If its too wet, give up or you will just smear the soil.