Do the tutorial.
Install Qlikview, making sure you check the box for 'Complete Installation'. This will install the Tutorial components.
Go to C:\Program Files\QlikView\Tutorial and open the file 'Qlikview Tutorial.pdf'. Follow the instructions and you are away!
After the tutorial, start building your own applications, referring to the Reference Manual (C:\Program Files\QlikView\Documentation\Qlikview Reference Manual.pdf) to increase your understanding of scripting methods, functions, sheet objects and other areas. It is also a pretty good idea to look at some of the sample applications, as Ravi has suggested. This is a good way to pick up 'best practice' modelling methods.