As most of you know, post stitches are not worked into the tops of other stitches, but rather are worked around the post of a stitch in a previous row. By being worked in this manner, they tend to be raised from the surface of the work and can therefore be used to create some very interesting textures, such as basketweave. In this bag, the treble and half treble post stitches frame the bobbles.
Remember to work these stitches fairly loosely, so that they don't pull the work out of shape. You can experiment with your tension until they look right. Please remember, there is no "right" or "wrong" when it comes to tension on these stitches, just trust your eye! When they lie nicely on the surface, not pulling at the work, they're just right.
In the first series of Front Post Stitches you encounter in this design, you have two post stitches worked into the same stitch. You mark the stitches in row 4 so you can find them when it's time to do the post stitches in row 6. You wrap the yarn the indicated number of times -- 3, since it's a treble stitch -- and insert the hook from front to back and then out the front again in the indicated stitch, then finish the stitch as usual.
Then you work the specified number of hdc before working the second FPtr, which goes into the same place as the first. Make sure you skip an hdc where instructed to do so. To place the second post stitch correctly, insert your hook BELOW the point where the earlier post stitch was made, as shown in the photo here.
The next Post Stitches occur in row 8. They are worked around the posts of the earlier post stitches, which are very obvious. Note that they are half trebles, and are worked off as described in the Special Stitches instructions.
The third group may seem a bit tricky, because you are working two FP stitches together. Keep in mind, however, that it's just like any other instance when you are working two stitches together: insert the hook where indicated, work off 2 loops on the first FPtr leaving the last loop on the hook, then insert the hook in the next indicated stitch, work off 2 loops, then yo and work off all the loops. Again, these should be worked quite loosely.
Some people have noted that the post stitches don't seem to frame the bobbles on their projects. It's possible that this is caused by miscounting of stitches on previous rows. Pay attention in particular to which stitches are skipped in the rows before, as this will also affect the alignment of post stitches. As mentioned in the last lesson, it's important to count stitches at the end of every row, and check that each half of the row is a mirror of the other -- this will insure that your bobbles and posts are in the correct place.
When I worked the project, my bobbles were nicely framed by the post stitches, and in one or two cases I moved the post stitches by hand around the bobbles. Feel free to do this if necessary (as in this example below).