Govia Thameslink Railway has published an Easy Ticket Guide to coincide with World Autism Acceptance Week.
Created with the input of 30-year-old Goring-by-Sea resident Josh Puglia, who has autism, the new guide gives practical advice for people living with the condition and others with anxiety, to help them travel.
Josh said: "I can't drive because I have autism, so being able to travel by train is so important to me - it gives me independence to travel to Brighton to the charity Grace Eyre which gives me and others with autism and learning disabilities support and where I'm an ambassador trustee.
"But it's really challenging. If it's really busy and there's a queue behind me at the ticket office or it's noisy then it makes me really anxious and I can feel overwhelmed.
"This guide will help others with autism see how they too can buy tickets and travel by train.
"And, hopefully, World Autism Acceptance Week will help other people understand my autism and give me the space that I sometimes need."
GTR operates Gatwick Express, Southern, Thameslink and Great Northern services and Josh has joined its Access Advisory Panel - a group of disabled volunteers who use GTR services and give the company practical advice on making improvements.
The guide explains the different ways to buy a ticket, including at a machine which may be
GTR Accessibility Engagement Manager Antony Merlyn worked on the guide with Josh and autistic colleagues at GTR. He said: "The idea to produce the 'Easy Ticket Guide' guide came when I first spoke to Josh after he joined our panel. Together we discussed how buying tickets can create anxiety and potentially present a barrier to travel for many disabled customers - not just those with autism.
"It's all about removing barriers to travel. This can take all shapes and sizes - it's not just about doing big things like installing lifts. This guide is a very simple idea which tackles a very real potential source of anxiety."
Passengers can download the guide from the train firms' Assisted Travel > Support While You're Travelling pages.
Another guide is being created to help people find the right train.