I like to travel. You can travel a lot even on a stipend (last year I went on 16 trips!). I get into a lot more detail below, but basically it's through a combination of: credit card bonuses, staying at hostels (or friends if you have any in the area you're visiting), and being flexible on when you travel (eg. flights tend to be cheaper on a weekday morning than Sunday evening).
Being a graduate student helps since you get to travel (in the pre- and hopefully post-coronavirus era) to attend conferences and workshops. Most conferences and workshops I've attended have had some money set aside in their budget to fund scholarships for students if their advisor is unable to fund them. Your department or graduate school might have some scholarships for this purpose too. In my experience, the sciences tend to be more generous about this than the humanities. If I understand the culture differences correctly, conferences are a bigger deal in the sciences than in the humanities, so I guess it makes sense? Networking always helps though, so I hope they become more generous with this!