Here's a guide for Testing Laboratory%.

After you spawn in the first room, run to very right side of the elevator. You need to be there just in time before House starts speaking. Afterwards you just skip his voicelines and you continue through the hallway. Here you can use first of many the jump edge glitches (Test 1,), which are located in all over the Testing Laboratory. To do it correctly, you have to jump on the very edge of the block which is located above your head. If you do the jump correctly, it will save you aproximately 0.040 seconds.

TEST 1

Skip the voicelines and you can try to make a Jump Edge Glitch (JEG for short). After you came to the ‘X‘, just tap the ‘Enter‘ or the ‘E‘ button to hold your breath for a brief moment, skip voicelines and continue to the next room. Here you can perform another JEG and press both buttons, one labeled with the number 2 and one with the number 10.

TEST 2

You can try to get another JEG and continue to the centrifuge. You can go out of it as soon as possible by spamming the 'Enter' or 'E' button on your keyboard. Continue to the next room. Again you can perform JEG here and climb up the broken elevator to proceed to next test.

TEST 3

After skipping some voicelines, you will came to the next test – jumping over the rope. Here you can stop jumping right after House starts his first voiceline. Be careful with skipping the next voicelines, it is possible to get a softlock if you skip them very fast in an incorrect way. Then just continue to the next room.

This room is very empty. You can't perform any JEG to save any time, so you just run through it to the text test.

TEST 4

After running to the ‘X‘ and skipping a voiceline, you only need to do 10 push-ups. After the 10th push-up, you will wait for a moment and Coffee Guy will stand up and you can continue to the next room.

Here you have arrived to the little staircase. You can do an JEG and then just try to jump through these stairs as fast as possible. It is very easy to hesitate and lose some time here.

TEST 5

You will arrive to the test with the treadmill. Skip the voiceline and jump on the treadmill. After House starts speaking, you are free to leave it, skip another voiceline and run to the next room.

Here you will arrive to another room with the buttons. To complete it in the fastest way, you just have to press the center button (wait till the hydraulic platworm reaches a good height) and then press the left button and run through it to the next test.

TEST 6

You skip the the first voiceline and again you can try to do a JEG. After you will be on the ‘X‘ don't try to skip the lines as fast as possible. For whatever reason, you can again either softlock the game, or House will run to the right, back to the left, press the button and so on, repeated - It takes around 15 seconds to recover from this.

Here you will arrive to the doors labyrinth. To leave it in the fastest way, you have to enter the 4th door in the first room, then the very 1st one in the second room, then the 2nd one in the third room and then the 1st door in the fourth room. Then continue to the next room.

TEST 7

Here is the microphone test. After skipping the voicelines, try to do a JEG and go on the ‘X‘. Here you will just press the ‘E‘ or ‘Enter‘ and skip the voicelines again. Then you can continue to the next room.

Here is the Infinite Staircase. The most precise part in the whole run. You have to reach the little stair in between the 8th and the 9th lamp. Then you can go back down. It is possible to gain super speed here by jumping to the left and then holding left and down. Coffee Guy can gain a ridiculous speed in a short moment that can send you right at the start of the room if you do it correctly. Then you can continue to the next test.

TEST 8

Arrive to the very bottom and then skip the voiceline. Afterwards you just complete the course once, and then you can go and continue to the next room. In this room, try to time your jump that you can fall as soon as possible to the next test room.

TEST 9

You will fall right onto the trampoline. Skip the voicelines and try to count to 20 and then you can go and continue to the next room. Also you don't have to jump by pressing the jump button. Literally don´t do anything and just count to 20.

Again like in test 3, there is an empty room that you just run through and go to the final test.

TEST 10

Arrive to House and skip his voicelines. Then stand on the ‘X‘ and now your last task is to skip all the upcoming voicelines between Professor Himmel and House. After you skip House's last voiceline ‘Damn it!‘, your speedrun will end here!

(Thanks very much to Pr4skyr09 who had the time to write this down and let me fix gramatical errors, etc. etc.)