While the previous surah tells us that everything depends on Allah, this surah gives us an example of how we depend on Him. The surah was revealed when the prophet became victim of a magic spell which was manifested by him seeing certain things that wouldn't be real. This is similar to what happened to prophet Musa when magic tricks made ropes appear to him as snakes.
The revelation of this surah is a clear proof that magic and envy must be real. Also the fact that the prophet was affected (before the revelation of this surah) means that none of us is exempt. But Allah, the merciful, will not leave us stranded without a way out. The recitation of this surah along with surat-un-naas and surat-ul ikhlas is one way to earn Allah's protection. In this surah we seek refuge in Allah, the Lord of falaq, the one that causes splitting and sprouting and causes our transition from darkness to light. We seek His protection against the evil of His creation, including the night which is the most fertile ground for dark forces to exercise their evil plots and deeds. Only Allah can protect us against magic and envy.
A way to minimize the likelihood of being a victim of hasad (envy) is to make sure we don't flaunt or expose our good things too much. Also saying maashaa Allahu, laa quwwata illaa billah (whatever Allah wills shall come to pass, for there's no power save with Allah) upon feeling hasad against others will help supress its effect.