The most Awesome looking way to enter Shadow Temple Early in ocarina of time
Superslide Teleport Method

It took me forever to record this in under 1 minut to fit in a YouTube short🤣

this tutorial is mostly copied from zeldaspeedruns.com check them out for more awsome glitches and tricks!
The footage is from my own gameplay on my Switch.

In order to teleport, you cannot have any of the strength upgrades in your equipment screen. Otherwise, when Link grabs the bush, he will just pick it up.

1. Activate ISG and have your sword sheathed.
2. Follow the setup in the video to get to the right position.
3. Destroy some of the grass, ensuring that you leave the bushes to your right and the one closest to the wall in front of you.
4. Stand just within "Grab" range of the bush in front of you and pull out a bombchu.
5. Hold about 50% of the way back on the control stick so that Link is walking backward.
6. After walking a couple of steps backward, press and hold R, followed very quickly by mashing A while always holding down slightly. Link will drop the bombchu and sideroll to the right.
7. Once you have the superslide, release and repress Z Target so you can see the bushes - this prevents them from unloading.
8. When you are at the top of the grave, release everything, and you will be teleported above the bush you tried to grab. Turn and side jump to the seam.
9. Be very careful walking on the seam because it's very easy to get stuck, but you won't fall down due to the ISG glitch. Just take your time.
10. When you are above the entrance, side jump over the loading trigger and enter the unloaded door to the Shadow Temple.

Good luck!