Speedrun Timer Overlay Help

[azzy]

I've recently been wanting to try Outlast with a Speedrun timer after successfully speedrunning it. The only problem is that I'm having trouble trying to overlay WSplit into the game. I've seen multiple people speedrun the game on Youtube with their timer overlaying into the game, so if anyone has any sort of guide as to how I am suppose to get the timer to overlay into my game, I would greatly appreciate it.