I need money

How can I make more money? I'm making my way up to the big cloud above rito village and I need 2 articles of clothing that protect against cold. Why is it so expensive? The shirt 500 rupees the Headdress 650 I don't wanna talk about the pants but lucky I don't need them. What should I sell? The sapphire is going for 150 and if I don't need it, I have no problem selling it same for the Ruby.