Trigger UPDATE from 'inserted'

Hello,

I am trying to create a trigger which should monitor the table tbUsers. Once a record is inserted into tbUsers it should update the column of the table tbWatch 'LastLogged' with the current date/time from the server and also add the value of 1 to the column 'TimesLogged'. The table tbUsers and tbWatch connect on the column 'MAC' so obviously the update should happen only if the MAC value from the rows to be appended on tbUsers match those of tbWatch.

Many thanks