"To get some rest" means to take a break and relax. It refers to finding time to unwind and recharge your body and mind by sleeping or doing activities that help you feel refreshed. Full definition
He couldn't get the rest of the leadership team to agree to develop the product the way he wanted to, he says, so he quit to do it himself. (inc.com)
One note: I did add a bit more applesauce because I couldn't get the rest of the flour to mix in. (chefsavvy.com)
You might worry that your exercise regimen and diet may not be enough, and feel that a pill would help get you the rest of the way there. (dietsinreview.com)