There are 2 ways to book your SGR tickets on phone.
Go online and and book on the SGR website.
This is by far the best way and the easiest way to make an SGR train booking. Go to https://metickets.krc.co.ke/ and make the booking. Here is a step by step guide on how to make the booking the SGR train booking.
Use the USSD code
This is an alternative way to book a SGR Train ticket. Load up mpesa on your phone. Dial *639# on your handset and follow the step by step guide. You can buy 5 tickets at a time. You will need to be fast to avoid the timeouts.