Proofing your own work is hard for most people. After all, you know what you intended to say, so that is what you tend to see when you proofread your writing. Proofing is a huge challenge for me, as you have likely seen in past posts.
I am much more likely to catch errors when I let my work sit for a day or two. With the distance of time, I am less likely to see what I intended to say and actually see what I really wrote. But this is not a guaranteed solution either. Plus, waiting is a luxury not afforded when blogging.
Another proofing technique is to read your work aloud. Yes, it is a bit strange at first, but reading it aloud does help you catch errors. A side benefit is this also aids in catching awkward sentence structure and poorly crafted wording.
A third method is to read it backwards. Yeah, I don’t get it either, but some people swear by this technique.
Also, I tend to proof better from a printout versus working directly on my computer. (Interestingly, when proofing on my computer, it makes a difference if I adjust the font type or size. I guess the change of perspective helps.)
But the best way is to have someone else proofread my work!
Regardless of how skilled or lacking you are at proofreading, be sure to spell check your final version. I am shocked at how often I receive submissions with errors that spell check would have caught. That is inexcusable.