I've often been asked for advice on loosening up and painting more intuitively...these are ten things I like to practice:
1. work standing at an easel or wall as that can help your body to loosen up instead of being seated at a table.
2. turn your canvas upside down - a new perspective is always refreshing.
3. work large so that you have to use your entire arm including your shoulder and not just your hand and wrist.
4. paint (or draw) with your non-dominant hand.
5. put on some inspiring music, maybe try something different than what you would typically listen to.
6. treat the work like play, don't plan to create a 'finished' piece as that can help take the pressure off.
7. draw quick loose sketches to get the right side of your brain working as it's the creative side that you want working for you, not necessarily the logical side.
8. close your eyes for a little while as you work - a few 'errors' can sometimes be just what the painting needs to pop.
9. sketching every day helps teach hand/eye coordination so that when you work you can trust your body to be more involved in the process plus it is excellent to get those creativite juices flowing.
10. finally, I tend to spend a lot of time with a cup of tea just looking at the work in progress instead of pushing myself and it - I find that I get creative ideas just doing this (perhaps by adding another color or seeing an image I missed before) and I realize that loose brush strokes and marks add so much interest which helps me trust in the process.