Using WCFtestClient.exe to test webservice

HI Im currently Using WCFtestClient.exe to test my webservice and it gives me the following error

The maximum message size quota for incoming messages (65536) has been exceeded. To increase the quota, use the MaxReceivedMessageSize property on the appropriate binding element.

i read online that we should update the buffer size in the client config file but how can i do that with WCFtestclient.exe