As a game author:
The most important thing I learned from the playtesting is that the thinking process as they were playing the game. I had Olivia and Tara tested my game. Both of them would like to have a clear instruction to guide them making decisions when they are playing the game. I was thinking that if I put the options on the bottom of the pages, players might not want to read the texts and directly go to the options part and make their decisions. So I put the options in the text randomly, instead seperated them from the description of the story. However, after I did the playtesting, I found that players prefer a more clear way to indicate them when they need to make decisions.
What surprised me is that people have different ways to digest information, which makes me to reconsider how to design the way to convey messages and choices for players.
As a result, I will organize the information differently. Instead of putting the options inside the story description, I will place the choices separately and give some reasons to help them make decisions. Also, I will reconsider how privacy affects people's lives in various ways, which helps me to develop my story and make it deeply and more meaningful.
I will give 3 pieces of advice to an author who is about to playtest a game: 1. try not to explain the story when a player is testing the game, even he or she has many questions; 2. be prepare that the player may have different mindset with yours; 3. observation of how the player plays is as important as asking the player's feedback.
As a playtester:
I learned the way how other game designers to make the story interesting and easy to read. I found that Olivia was very good at making the story dramatical intense and Hridae constructed the story in short sentences which was easy to read. Also, Hridae showed the backstory clearly and kept the game moving on. That's what I was trying to do but didn't find the way.
Being a playtester helps me to understand more about the playing process and how other game designers work on the project. My own game seems too difficult to read and less dramatic compared to them.
3 pieces of advice I would give someone who is about to playtest a game: 1. be patient to read a long passage in a time; 2. put your feet on the shoes to help the designer; 3. tell the designer what your don't understand in an appropriate and acceptable way.