Hello, I am seeking a bit of help with how to file a tax return at the end of the tax year 16/17 that is approaching. I am a full time teacher, therefore is selling resources classed as a second income? I have searched the FAQ section, however it is quite confusing and some information contradicts. Do I need to create a gateway account through HMRC (I thought this was just for self-employment?) or do I simply declare my extra income using an online form at the end of the tax year? TIA, From a very stressed out seller!