Despite how it feels, the situation is not hopeless. The most successful leaders have found a way to maximize their own productivity even in the face of infinite demands. How? First and foremost by adopting a mindset that "My time is the most valuable resource I have and therefore how I use it determines my success."
In order to make this process work, it is essential that you write out these three main focus areas before cluttering your mind with "reactive" tasks such as checking email, voicemail, or social media. It is vital to prioritize what you want to achieve before being inundated with other peoples' needs.
I've never been good at setting boundaries. I'm a giver and end up doing things I hate or spending time with people who I don't enjoy being around simply because I feel obligated to do so. This time management exercise is helping me set boundaries as well as come to appreciate the things and people that matter most to me.