How to caramelize white sugar without burning it?
It is perfectly normal for sugar to turn dark brown when making caramel. If it turns even darker, it is because it has been burning too hot.
The final temperature should be around 234 F, so you want to get there gradually.
As for the color, many recipes call for cream to make it smoother and tender, but only incorporate it after the crystals are fully dissolved and you're ready to take it off the burner.

I've seen a few youtube videos with just sugar and water for sugar cages...