Most newer Netgear devices have UPnP enabled by default. However there may be the odd model that doesn't work well with UPnp in some circumstances, thus port forwarding is way to go. Very first & most important step in port forwarding is to set up a Static ip: Static ip instructions (click link). Then do the steps in the link Remoc gave you.

Also go to LW's menu bar, Tools > Options > Advanced > Performance & disable all options there. Some users have had problems connecting with those options. After they connected those options could then be re-enabled.