For most verbs, you form the present participle by adding –ing to the end.
[main verb] go
[present participle] going
However, there are some special rules for words ending in -c, –ie, or a silent –e, as well as for words ending in one vowel and one consonant.
For verbs ending in –c, just add a -k before –ing.
For verbs ending in -ie, change the –ie into a –y before adding –ing.
For verbs ending in a silent -e, simply drop the -e and then add –ing.
Please note that this does not include words ending in a double –e. Verbs that end in –ee follow the standard rules.
For verbs ending in one vowel and one consonant, double the consonant before adding –ing.
There are exceptions to this rule, however. If a word ending in a single vowel and a single consonant has two syllables but the second syllable is not stressed, you can add –ing without changing anything.
(In UK English, if a word ends in a single vowel and an l, like cancel, you double the l before –ing, as in cancelling. In American English, you would use canceling because the second syllable is not stressed.)