Have you always struggled with spelling words correctly? Would you be lost without the spell-check feature? There is one trick with spelling that I have taught students young and old: Find the word within the word that you know how to spell, then work on the parts you don't know.
For example, the word reconfigure. You may not know how to spell configure or figure, but maybe you know how to spell fig. Start with that simple word and add onto it. Most know the spelling of "re-", and the word "con-". Now you have reconfig-. If you sound out the ending, you should be able to add the '-ure" without any trouble.
Unfortunately for many, this "trick" isn't even considered until later in life and many have already become super reliant on the spell-check (our technological savvy generation, right?).
Tackle those big words one little step at a time. Take those bigger words apart to make smaller pieces, and you'll be on your way to better spelling and more impressive writing!