Installing opencv on ubuntu

Hey,
I am new to ubuntu(got it installed 3 days ago) and I wonder if anyone could help me with setting up opencv on it. First of all I will tell you all I have done but just know that most of the time I had no idea what I was doing… I followed few advices on installing tar.gz files from google.

  1. I downloaded the .tar.gz file from their website: http://sourceforge.net/projects/opencvlibrary/files/opencv-unix/2.4.5/
  2. I extracted it using tar -xf
  3. I used cmake on CMakeLists.txt
  4. Then I typed inside the directory ‘make’ and after it was done I did ‘sudo make install’ and this is where I am stuck now.