This is me. I always have to repeat the little rhyme to myself:
I before E, except after C,
Or when pronounced “ay,” as in “neighbor” and “weigh.”
Or on Sundays and holidays
and all throughout May
And you’ll always be wrong
no matter WHAT you say!
their :rolleyes:
when I type fast the “I’s” seem to get pressed first.
a second would be things that end in “LY” or “LLY”, “ALLY” “LIE”
Mine are almost always typos, because I get paid for knowing how to spell, among other things. Words that I just cannot seem to type correctly are those that end in -ion. I always type them “ino,” so “mention” turns into “mentino,” “accommodation” become “accommodatino,” and so on.
If I were speaking for my students, I would say the word they have the most trouble with is “definitely,” which almost always become “defiantly,” either because they originally type it that way or because they change it after doing a spellcheck.
Remember–there’s “a rat” in separate! 
amount (ammount)
the (hte)
I always have trouble with:
[ul][li]recommend[/li][li]occasionally[/li][li]accommodation[/ul][/li]I can never seem to get the double letters in these words in the correct place.
I keep getting letters from this idiot contractor at work who consistently spells “intention” as “intension.” :rolleyes: The spell check included with Office apparently doesn’t catch it for him, because “intension” actually is a word, albeit an uncommon one, and not the word he intends to use. (Note that this contractor is an idiot for reasons other than his inability to spell.)
I’ve always been an excellent speller, but lately I’ve been having trouble typing words that contain apostrophes. Not a spelling problem, but a typing problem. My fingers just want to put the apostrophe in the wrong place.
And there are no a’s buried in the cemetery!
When I’m typing quickly, I almost always type “guide” as “guild” (too much WoW, I guess). Also tend to type “field” as “firle” (no idea why). Also the standard “brain moving faster than fingers” typos like “teh” and “thikn”.
As far as words I misspell consistently–there aren’t many (except for typos–I make plenty of those!) The only one I can think of off the top of my head is “LaBeouf” (the actor’s last name). Not that I have many occasions to type it since I don’t even particularly like the guy, but I pride myself on my spelling and I canNOT remember what order all those vowels come in!
Time to channel Michael Scott – convoluted tricks I have for remembering three of the words that’ve been mentioned here.
First, I de-fin things nitely, then I take away an “n”: De – fin – nite – ly. Definitely
I rest the gold rant: Rest – Au (symbol for gold) – rant. Restaurant.
And while we’re ranting, I take Guar (which I get to my remembering the band GWAR isn’t from Guam), and make them my rant-ee. Guarantee.
Not a misspelling, but then/than - I always type the wrong one. Don’t know why, I know which one should be used when, but I just write the wrong one when I type.
Heirarchy and Carribean.
And minuscule.
is apparently another word you often get wrong 
Anyways, I have a tendency to leave out the s at the end of plural words. I also tend to leave out words if I wind up thinking the words too much faster than I type. I’ve actually gotten into the habit of reading my stuff aloud as long as no one can hear me.
I also have this annoying habit where, if I mistype a word, I can’t think how it should be spelled to fix it. Yet, if I hadn’t typed it wrong already, I could have spelled it correctly.
separate
My biggest problem is homophones. Eye no and can here the diffrance fein butt in Tai Ping will swerve like a drunk twixt spellings.
Property - Proeprty - Since I work in real estate, I spell this wrong about a dozen times a day.
Outstanding - oustanding
Broswer.
Pronounced brozz-wurr. Like this thing I am looking at the SDMB on right now.
Inconvenience - unfortunately when I mess it up in work the Microsoft Word suggestion is incontinence, so instead of apologising for any inconvenience our error may be caused, I apologise for any incontinence we may have caused 
I have spotted it just before posting a few times but I just know I’ll get caught out one day!