The final colour depends on the variety, dino. Most start out green with red probably the most common end result but you can also have green, yellow, brown, whatever.
One test for maturity is the stem connection between the fruit and the plant. As the fruit nears maturity, the stem connection dries out and weakens. The fruit will come away with barely a tug. You can also feel the fruit itself. If it's hard, it's not ready. If there's some give, and you can feel some space inside - where the seeds are - it's pretty ready.