"That being said, if your trying and saying positive things to yourself, how do you ignore any other thoughts creeping in?" - chuff
You're mixing them up. We have Relaxation, Meditation, Visualisation and Affirmation. Relaxation, Visualisation and Affirmations can be used together. But Meditation should be done on its own. Cultivating positive thinking is something that can be done during relaxation and visualisation, using affirmations to re-enforce the concept. And any thoughts that 'creep in' can be converted to positive thoughts or simply ignored.