Book early: For popular events like Oktoberfest or major trade fairs, rail seats go quickly weeks in advance. Book as early as you can to secure the cheapest saver fares. Domestic DB tickets are usually bookable up to 12 months ahead.
Plan the return: Many travellers book only the outbound leg and sort out the return on the event day, but late trains are often sold out on event days. Book both legs together, ideally with a bit of buffer on the way back.
Consider the Deutschland-Ticket: If the venue is reachable by local transport, the Deutschland-Ticket can be the cheapest option. It covers regional trains, S-Bahn, U-Bahn and buses, perfect for day trips to nearby events.
Watch for special services: Rail operators often run extra trains and services for major trade fairs and festivals. These are sometimes cheaper than regular long-distance trains. Check the organiser's website or the relevant rail operator.