Participles

verb base +ing

be – being
draw – drawing
play – playing

Exceptions:

ending silent -e, drop -e, add +ing
drive – driving
come – coming
write – writing

ending -ie, change -ie to y, add +ing
lie –  lying

ending –ic, add +k, then +ing
panic – panicking
frolic – frolicking

ending – l, double -l, then +ing
travel – travelling
grovel – grovelling

one syllable and last 3 letters are 
consonant, stressed vowel, consonant:  – double the last letter then +ing
stop – stopping
begin – beginning

more than one syllable and last 3 letters are consonant, stressed vowel, stressed consonant: – double the last letter then +ing
occur – occurring
refer – referring
begin – beginning

Uses:

to form the continuous (progressive) tenses
She was boiling water.

as adjectives
The boiling water scaled her.

as adjectives, they may  from compound nouns
walking stick, wedding dress, racing horse.