"Reserve searing on trains if you're travelling by train, you can do that on the trainlines' website," said one girl.
If you didn't reserve a seat, she warned, you would end up "sitting on the floor for four hours".
2. Know the difference between hostels and youth hostels
Regarding accommodation, the pair said people should understand not all hostels were the same.
"We thought hostels were only full of 20-25-year-olds but there's a difference between youth hostels and hostels." She said. "All of the hostels we've stayed in .. well, three out of four have been with adults and grown men."
In response to comments, Nada clarified that there was nothing wrong with adults staying in hostels, but their group didn't feel comfortable.
"It's just we are young girls who feel safer staying in a room full of strangers who are women over strangers who are men," she wrote.
3. Don't believe everything on social media
Ironically, the third tip was to take social media content with a grain of salt before going to Europe.
Don't pay too much attention to TikTok cause of romantic stuff so you show up to a bar like Lucerna and be severely disappointed.
4. Buy a belt bag
The next nugget of wisdom wasn't a mistake, Nada said, but a tip.
"Buy a lulu belt bag like all of us," she said, panning the camera to show each of the girls sporting the popular cross-body bag.
"It keeps your stuff on your chest and no one can steal it off you."
5. Validate public transport tickets
Short and sweet, the girls warned people to validate all public transportation tickets.
However, other travellers agreed this rule had caught them out.
"I almost got arrested in Budapest because I didn't do it," wrote one viewer.
"That happened to me in Budapest too. I had a ticket but didn't validate it and they had those people at the exits," said another.
After purchasing a ticket from a self-service machine, people must take the printed ticket to a validation machine, where it is validated with a date stamp.
This must be done for train and bus tickets in many European countries.
6. Wear black in Berlin
The final piece of advice was about what to wear if you wanted to get into Berghain, a Berlin nightclub that is notoriously exclusive.
"Wear all black head to toe if you want to get into Berghain or else you'll get denied," one girl said with a grin.
In the comments, travellers asked to know more about how to get into the club, but Nada said they only knew tips from other people as they were denied entry.