To be truthful, I used to undervalue those that I considered to be of lesser intelligence than me. This was a feeling born of pride, and although I occasionally find myself falling back into old habits, I am happy to say that God has granted more than a little success overcoming this particular fault.
There are a couple important things to remember if you have this issue.
#1: There is always someone smarter than you, period. There is no “Smartest man alive” because knowledge extends into more fields than a single person can possibly cover in their lifetime. You may be a genius in astrophysics, but know next to nothing about molecular biology, or how a car works for that matter, or how to cook, or how to keep accounting records, or any one of a trillion other tasks which are important and necessary for the world to function. No matter what, someone, somewhere, is better at something than you. Always remember that, and it will help you quite a bit.
#2: Always, always, pray for humility. Humility is not a virtue than can be gained by sheer force of will, you need God to make it happen, so keep asking for that help.
Hope this helps, God bless!