1. You will need planning permission for commercial use in order to do this and make sure you comply with building regs . Speak to the planning team at your local council
2. do some market research to look at demand and pricing in your area for similar places
3. Run a profit and loss budget - how long will it take you to recoup your investment bearing in mind your ongoing operational costs
4. read up on how Airbnb works useful tutorials and guides on this community and FAQs on the Airbnb Help Centre