These basic tips for setting your wooden fence posts into concrete are simple, quick and easy to follow.

Making the Post Firm
That is why you are using concrete.
The hole should be 2 feet deep and at least three times as deep as the post is wide.
Use a post with straight sides and a flat bottom to add strength.

Avoiding Early Rotting
Use pressure treated or tannalised wood.
Do not have the end of the post in a pool of water. Concrete under the post to protect the end grain.
Finish the concrete above ground level and make the top of the concrete convex so water runs away from the post.
Put a cap on the top of the post so the end grain is not open to the elements. It is easier to replace a cap than a whole post.

Keep Posts Firm and in Line
Align the posts with each other using a string or rope line.
Use a spirit level to ensure the posts are upright
Allow the concrete to harden before attaching the rails or panels.
Support the post until the concrete dries with couple of timber props at either side.