Making a garden lawn

 Hi, I have a small front garden approx 60 sq.metres and wish to make it into
a lawn (We already have a fair sized rear lawn). At present it contains
various bushes, shrubs and plants which will all have to be taken out.

Having done that what is the best way to proceed?   I hear various advice.
Should I put a membrane down to discourage weeds coming through, or apply
strong weedkiller etc?

Any advice gratefully received as I have never attempted this kind of thing
before.

Regards
John

 John wrote:

I did this to make a lawn just less than 100sqm.

Removed everything. At the end of August I used Roundup on the existing
grass. After 4 weeks the grass had all died and gone yellow but the
roots still bind the soil fairly well.

Then I double dug the lot by hand and turned the grass to the bottom of
the trenches. I then raked it and raked it and raked it to a fine tilth,
not dust but fine and finally watered it well before seeding it with
fine lawn seed, obviously you need to select the seed for your
circumstance.  By the end of September following regular gentle
watering... don't waterlog the ground... there was a fair covering of
grass and no weeds. Over winter there was little growth but come the
following spring the grass went mental and the lawn is great. Nearly a
bowling green :) A satisfying project.

Simon