Welcome, please start by the following test : http://helloquizzy.okcupid.com/tests/progressive-matrix-test-challenging
To get a short introduction and some training before taking this one.
Matrix difficulty range from hard to «Have I to guess» or «All answers are valid» difficulty.
Low score here are NOT a shame.
This is not timed and if you really took the preceding test, you should already know how to avoid pitfall.
If you don't, take it ! It's the last warning before you proceed.