Read from the End to the Beginning
The final product you share should not distract readers with any errors. A good way to proofread for spelling is to read from right to left, from the bottom to the top of the page. If you read only from the beginning to the end of the paper, you may overlook typos. Also, as you discover spelling errors, keep track of those. You can keep a list of common misspellings taped to the front inside cover of your dictionary so that you don't have to look up the same words over and over. Or you can tape short lists of words to several books you carry with you during the day. Just by glancing at the list from time to time, you can learn to spell the words correctly.