Hi Ruth, Firstly I would have some blonde highlights a cool blonde, this way the will add dimension to you hair, make you natural colour appear darker which in turn will compliment your brows, skin tone and eye colour. If the highlights are bleach they will also help the hair feel thicker and fuller. ...More >
Secondly the cut, having the sides of your hair shorter and a side fringe will show off your cheek bones and a soft layered/textured edge around jaw length or slightly longer will soften your chin.
See above, you can of course opt for longer and shorter version of the above style, but it sounds perfect for you. Good luck, have courage and go for it!