tell her you are going or doing something she probably have no interest in.
horse racing?
go join a gym?
treat her to a shopping trip abroad!
introduce her to some of your geekiest friends! give her an impression that you are a good boy!
take her fishing, and let her sit there for hours while you make it seem like you enjoy it, then suggest to go again the next week!
will need to carry alot of stuff with you though
thats whn the gym membership comes handy