The safest way to get rid of slugs is by using cornmeal. All you need to do is to pour a tablespoon or two of cornmeal in a container. Then lay it on its side wherever there is slug activity. The snails will locate the cornmeal and get inside the container to eat it. When they get inside, you can dispose them off. Visit http://www.wikihow.com/Get-Rid-of-Garden-Slugs for more information.
"One problem that seems to bedevil gardeners is an ongoing problem with snails and slugs. How to get rid of them and grow organically only intensifies the problem because it requires a long term solution. No quick solutions without throwing down chemical snail and slug death.
I once asked a gardening teacher how she got rid of snails and slugs, and she told me the best solution was to hand pick them off. I had tried putting crushed eggshells around plant stems to deter them (in my case, not effective), putting out beer in small containers (which attracted them to crawl in and drown, but eventually got diluted by the irrigation system), and copper (expensive!!!).
But what to do with them after picking them off? We used to give them to the ducks down the street, but they disappeared, so I put them in the green bin where they waited for any chance to escape. I then tried putting them in an evil neighbor lady?s yard. Besides the ducks, these methods were unsatisfactory because they seemed to return. I eventually decided to throw them in the street. I remembered a Tibetan co-worker telling me, as I cooked some live crustaceans, that I would get half the karma for killing them, and the restaurant would get the other half. Here, I figured I would get half for putting them in the street, and the car driver would get the other half.
I mostly picked in the mornings, and sometimes in the evenings with the assistance of a flashlight. I found that they liked to congregate in the same places: under certain plants, by certain walls, and on certain planters. I kept at it for three weeks and finally noticed a definite decline in the population. Now I still see occasional snails and slugs, but our plants are definitely less munched."
there are several ways but no way to get then all unless you remove their food source....beer traps...take a pan or cut off the bottom third of a 2 liter soda bottle....add some beer and put a stick or board as a ramp...the sails crawl up and fall in...another is diatomaceous earth....you can get it at most plant nurseries...and spread it around and the sharp parts of the D-earth puncture the snails....will do the same on other things like fleas and ants.....but you will have to reapply it after rain....another is EscarGo....it is not supposed to be harmful to pets....place a board on the ground and in the morning turn it over and drop the snails in some soapy/salty water.....if you have kids and they aren't squeamish you can make a game out of it and take them out at nite and pick up all of them you see