Despite the Masuda method being quite effective in Generation VII, breeding for shinies still takes a lot of time especially if you're aiming to get every possible shiny Pokémon out there. But just recently, a glitch in the Pokemon Sun and Moon breeding system was serendipitously found and is now trending on the internet.
Pokémon Sun and Moon: Shiny Breeding Exploit
A glitch in the system enables players to transplant - or technically speaking; swap the nature, gender roll, IV inheritance and shiny status of one Pokémon (regardless of specie) to another one by simply resetting the game. Although it entails traditional breeding method, this exploit hastens the process of obtaining a shiny Pokémon for up to 8x the normal rate (depending on the specie you're trying get). Here's what you need:
Magikarp
Ditto (preferable foreign)
Shiny Charm
Destiny Knot
The Pokémon you wanted to breed as shiny
Process:
Step 1: First, you need to save your game.
Step 2: Place your Ditto equipped with Destiny Knot in the nursery along with Magikarp (this Pokémon is essential as it hatches faster than any other Pokemon in the game).
Step 3: Collect 30 eggs
Step 4: Remove a parent from the nursery in order to halt egg spawns. The reason for this is because you will be saving shortly. Keep in mind that if you save the game while the nursery worker is holding the egg, you will not be able to change that egg.
Step 5: Hatch all 30 eggs
Step 6: If you didn't manage to get a shiny from the first batch of 30 eggs, repeat Steps 1-5. If an egg contains a shiny, proceed to Step 7.
Step 7: Remember or ideally take note which egg was the shiny. (i.e. 12th egg).
Step 8: Reset the game. DO NOT SAVE.
Step 9: You will now do the "swap." Place the Ditto, equipped with Destiny Knot, in the nursery along with your desired Pokémon (e.g. Wimpod).
Step 10: Collect 12 eggs
Step 11: Hatch the 12th egg.
Step 12: Shiny Wimpod!
Pokémon Sun and Moon: Shiny Breeding Exploit
A glitch in the system enables players to transplant - or technically speaking; swap the nature, gender roll, IV inheritance and shiny status of one Pokémon (regardless of specie) to another one by simply resetting the game. Although it entails traditional breeding method, this exploit hastens the process of obtaining a shiny Pokémon for up to 8x the normal rate (depending on the specie you're trying get). Here's what you need:
Magikarp
Ditto (preferable foreign)
Shiny Charm
Destiny Knot
The Pokémon you wanted to breed as shiny
Process:
Step 1: First, you need to save your game.
Step 2: Place your Ditto equipped with Destiny Knot in the nursery along with Magikarp (this Pokémon is essential as it hatches faster than any other Pokemon in the game).
Step 3: Collect 30 eggs
Step 4: Remove a parent from the nursery in order to halt egg spawns. The reason for this is because you will be saving shortly. Keep in mind that if you save the game while the nursery worker is holding the egg, you will not be able to change that egg.
Step 5: Hatch all 30 eggs
Step 6: If you didn't manage to get a shiny from the first batch of 30 eggs, repeat Steps 1-5. If an egg contains a shiny, proceed to Step 7.
Step 7: Remember or ideally take note which egg was the shiny. (i.e. 12th egg).
Step 8: Reset the game. DO NOT SAVE.
Step 9: You will now do the "swap." Place the Ditto, equipped with Destiny Knot, in the nursery along with your desired Pokémon (e.g. Wimpod).
Step 10: Collect 12 eggs
Step 11: Hatch the 12th egg.
Step 12: Shiny Wimpod!
Let me know if this works for you! 
+ Reps
