how to create a vacuum?

Hi.

For a physics project, i would like to determine the correlation between the boiling point of water and the air pressure.

As a demonstration, i was thinking about making a glass of water boil at room temperature.

I live in the tropics...so that will be around 30 degrees centigrade.

For that I will need to create a vacuum. and have my glass of water inside that vacuum.

Is there a way that can be done..with a vacuum pump for example.. but nothing too expensive...

How low would the pressure have to be...would it be possible??

If not...do you have alternate solutions??

Thank You