re singing + selling ballads - probably begging (busking) + selling 1penny broadsheets of the words (pity they didn't go with him to Australia as they can fetch reasonable sums these days!) probably in contravention of one of the vagrancy acts (beggars were common in Douglas in the 1830's - times were very hard).

Labourer covers anything - basically she had no fixed employer and thus did any job offered her.