In this thread about hard to spell words, words with doubled letters are coming up a lot. Things like “embarass”, “occurred”, “accommodation”, “recommend”, "misspelling ", etc. The normal error is doubling what should be single letters or singling what should be doubled letters.
Are there any tricks to remember these? I’m pretty good at spelling but whatever system I subconciously use just fails for this kind of thing, and I end up looking them up or using synonyms I can spell.
I have a trick for ‘embarass’: if my ass (double s) were out in a bar (single r), it would embarass me.
Why did you come up with a trick that helps you spell embarrass incorrectly?
As to the OP, many words with two questionable letters have a single one of the first and a double one of the second. However, most of the examples in the OP prove to be exceptions to this (including “embarrass”).
Maybe so I could emabarrass myself more frequently? :eek:
Being quite successful, I see. 
There really isn’t any ‘trick’ involved in learning how to spell these (or any) words; familiarity with words from reading is the only certain path. Rules like “i before e except after c” have enough exceptions to be nearly useless; they only point roughly toward general trends in a language.
With that said, some help can come from studying the components of words, in particular prefixes. You’ll never misspell “misspell” once you learn to instinctively break out the prefix “mis-”. Alas, not all prefixes are this simple (e.g. my knowledge of Latin is invaluable in understanding the formation of words that use the ab- or ad- prefix). I guess I’m left only to underscore the original point: familiarity with the words themselves from reading and general use is the best path to better spelling (and a richer natural vocabulary).