There are 3 common methods of anchoring footings for decks. J bolts, wedge anchors, and epoxy anchors can all be used depending on the depth of the footing and the size of the post. You may want to consult your local building department or lumberyard to find out which method works best in your area.
Installing J bolts into wet concrete is the easiest and most common method. First you need to locate the anchor position where the post will be installed to line up with your beams using a string and stakes. The closer you can set your J bolt to the center of the footing the better. Because you are dealing with wet concrete you will only get one chance to get this right. Once you have poured the wet concrete into the form tube you can set the j bolt into the wet concrete so that about 1" of the treaded bolt extends above the surface of the footing. Use a level to make sure the footing is straight. Clean off the top of the bolt and wait about 30 minutes for the concrete to dry. The bolt should now be securely fastened to the concrete footing and allow you to attach your post base connectors