I would like to apply for a Schengen visa to travel to Florence, Italy between 30th June to 8th July where I will be attending EuroPython. My request for the grant has been approved by EuroPython committee so accommodation and lunch are totally free for that period. For the visa there is a requirement for 3 years income tax returns, but I start to work last year and I don't even earn enough to file an income return. I would like to know how can I get a visa without an income tax return or what substitute documents I have to submit for the same.
You should not apply for a tourist visa, but apply for an "invitation visa" instead. You ask the EuroPython to send you an invitation letter and then use that to get a visa. The invitation letter should be in Italian.