securing a Garmin or TomTom type satnav GPS system to the dashboard or windshield

[yaris2014toyota]

How do you secure your Garmin or TomTom type satnav GPS system to your dashboard or windscreen?

In my case, it sticks via vacuum suction to the windshield for a short while, but falls down when the temperature changes. Not enough vacuum suction.

Also: I'd appreciate ideas on "where" to place it. I find that if I place it on the dash directly behind the steering wheel, I get the best visibility during the day, but the light (and its associated reflection on the windscreen) is distracting when it's dark outside.