If you're over 60 and have or buy a railcard, you shouldl save more than the card costs, with the rest of the 12 months to save more if you decide to use the train again.
Same discounts with Two Together and friends and family cards.
The Trainpal App generally gives you a discount on the cost of the card so you get it for £27 approx instead of £35 for a year. Plus it gives you an additional 5% off your first booking.
Moneysupermarket is the place to look for the discount codes.
This week i'm going to London for £13 return, next week i have another trip to London booked for £7.85 return. Standard return price without a railcard is £37. I also got an Oystercard as I go to London fairly often, I've linked the railcard and oystercard so I get 1/3 discount on off peak public transport in London.
https://www.moneysavingexpert.com/deals/railcard/