In gameplay, go to the thrill store (thats on the top screen) and tap the staff button Tap
the staff button with a wrench next to it. Tap that.

It costs you $350 to hire one.

You can buy workers.
You still have to fix them though...

press the L button to switch screens then on the bottom screen tap on the shopping cart to
bring u to the thrill ville shop. You can buy cleaners and mechanics for $350 and
entertainers for $250 once hired you can tap on the staff and then play a minigame to
level them up so they can fix bigger rides like coasters and that

you nedd at least 2 mechanics and 2 groundskeppers at max proficiny and still it has a
limited amount of rides 15 after that you have to clean them your selves you can check if
you click the eye gl*** on the ride and look at the top there is a small pic of a wrench
and bucket if you have enough there will be a green check mark by it