Open the profile menu, select Settings, then Preferences.
Appearance
Dark or Light. The description is Switch between dark and light mode.
The choice follows you across the whole site, including these help pages and the blog, because they share the same stored preference.
Display size
Five steps: Smaller, Small, Default, Large, Larger. The description is Make the whole interface bigger or smaller.
This scales the entire interface rather than only the text. It is the setting to reach for if the simulator feels cramped on a small laptop, or too small on a large monitor. Pushing it above Default can make the layout wider than the window, which is intended: the content then scrolls.
Language
Twelve languages. The interface, tickets and emails all follow it.
One deliberate exception: the authentic system identifiers inside the simulated tools, such as event source names and event IDs, are not translated. A real event viewer does not translate them either — they are the same in every language — and being able to search an event ID is part of the point. Everything a real localised tool does translate, the simulator translates too.
Sound
Enable voice calls, message playback, and spoken guidance.
Turning it off silences the voice features. If calls are silent, check this first. Browsers also block audio until you have clicked somewhere on the page, so a click and a retry is the other thing to try.
Hints
Show hints controls whether the I don’t know how to fix this panel appears on tickets. The description is Show the “I don’t know” hint button on tickets.
Turning it off does not change scoring. Hints never affected your score in the first place. It is there for people who want the temptation removed.
Difficulty and ticket focus
Also on this tab. See Choose which tickets land in your queue.
Where your preferences live
This splits two ways, which is worth knowing before you set things up on a second machine.
Sound and Hints are saved to your account and follow you when you sign in elsewhere.
Appearance, Display size and Language are stored in the browser you set them in. They do not travel with your account, so a new browser or a new machine starts at the defaults and you set them again there. Display size is per-device on purpose, since the right size for a laptop is rarely the right size for an external monitor.