how do i trace my remote machine Activity through wireshark

First of all, you need to capture the packets the remote machine sends and receives. Maybe this URL can help with the basic setup to do that:

http://wiki.wireshark.org/CaptureSetup/Ethernet

If all else fails you could install Wireshark on the remote machine, but that is always a "last resort" action since it will not always give correct results. Maybe you could also use rpcapd, which is part of WinPCAP (if your remote machine is a Windows box), but while allowing convenient remote captures there are some drawbacks and additional Wireshark configuration work to be done.