You could go out at night with a torch and collect them by hand. Put down bird food (seeds or sultanas) to encourage the black birds or thrushes to eat the slugs. Sink some jars in the ground near the lawn edges with a drop of beer in them. The slugs will enter and fall to the bottom and drown. Cut the bottoms of washing liquid containers, leaving about four inches. Cut some small door-ways and place over a small pile of slug pellets. This will keep them from being washed away by the rain. The slugs will crawl inside and eat them. Unfortunately the old metaldehyde pellets worked well but the new ones don't seem too good.

Thank you. I will take your advice.