Videos of mine on how to solve sudoku:

https://www.youtube.com/watch?v=t6CgSiUrmu4

https://www.youtube.com/watch?v=1qlgMgOoKvM

https://www.youtube.com/watch?v=q1XnPi8eXOg

https://www.youtube.com/watch?v=pPpPz_Q0wdE

And if you are stuck with no more moves:
https://www.youtube.com/watch?v=OCDkTstcxSY

Sudoku Lesson Begining

The lessons for Sudoku are several. However you
will use these techniques simultaneously when solving a puzzle. The
trick is to make notes at the top of the squares when you have a number
narrowed down to 2 possible squares in a box. We will name the boxes
for our lessons this way:

So the boxes are named TopLeft (TL) etc. The "Box" is the
larger square with the 9 smallest squares.

Rows go across sideways and Columns go up and down.

I do not remmend putting all the possible numbers in a square that
could possibly go in it.

There are too many numbers all over the place and you cannot see what is
important.

The main techniques are

1. Same number in 3 boxes

2. Putting numbers in 2 squares

3. Locked squares

4. Finding missing numbers in Columns/Rows/Boxes

These are done many times simultaneously. We will go over these
techniques but many times look at

two or more of them at the same time.

When you are feeling stumped, keep going back over comparing numbers
1-9 in different boxes.

Then try finding missing numbers in rows or columns and see if you can
eliminate them comparing the opposite

direction. After that, look at the numbers missing in a certain
box of nine squares and see if you can find where they go

or if you can find some squares that can be "locked up".

video 1 of example on how to solve a puzzle

video 2 of example on how to solve a puzzle

video 3 on a way to help solve it if stumped
and no more squares can be solved.

This will solve all but the most impossible "evil"
puzzles. If stumped, then copy the puzzle,

pick a number that is in two of the squares of a box, and put it in one of the
squares. Continue to solve the puzzle and

if you find it does not work, then take the copy and choose the other
square.

LESSON 1-8
Click here for lessons

After finishing the lessons, try these examples.

Example 1 video
click here

Example 2 video
click here