You have to give more information(think garbage in = garbage out).
What OS do you use? or have access to?
Are you running anything on a virtual machine?( think emulated OS)
What is your skill level/knowledge?
Are you looking to run it 24/7 with WEP or just while ds lite is in use?
Does your router have a guest network setting? If so, you can do that but also enable MAC filtering to prevent anything other than your DS from connecting.