Interfacing puckers

Frequently when I interface a thin fabric, say a thin quilting cotton, the fabric puckers after I use fusible interfacing.

I'm really careful and press the iron up and down, I don't slide it across the fabric.  All looks good until I pick up the fabric off the ironing board and then I see the wrinkles/puckers.  If I look at the back of the interfacing I don't see bubbles, or obvious mistakes I've made.

I mostly make bags/pouches, and I don't like a really stiff bag, so I am using a light weight interfacing.  I'm starting to think that with a thin fabric I need to use a stiffer interfacing, or none at all?

I tried to take pictures to show what's happening, but my camera isn't good enough to capture the details.

Do you have a favorite technique for using light weight interfacing with light weight fabrics?    Or, am I simply using the wrong product for the job?

Thanks!
Cindy

I'm not sure about the "right" way to do it, but I use lightweight fusible all the time and my first suggestion would be to not use a contemporary ironing board.  I'm not sure what you're working with, but I just have a generic Target ironing board and, while it's great for ironing my clothes, I find that it's just not a good enough surface for sewing projects.  I have a quilter's pressing board that I use for everything and I like it a lot better than my ironing board.  I get much better results with fusibles in particular, because it's a harder, smoother surface.  Another suggestion would be to press from the fabric side, instead of the interfacing side.
 
Here's the pressing board I'm talking about:
http://www.joann.com/joann/catalog.jsp?CATID=cat2690&PRODID=xprd74140&source=search
(I don't ever use all that gridwork on it -- It isn't very straight anyway!  It's a great pressing board though.)

Preshrinking your interfacing should solve this problem.  I usually put hot water (from the faucet, not boiling hot) in the sink and soak my interfacing for about 20 min. Drain the water and skwish the interfacing (don't wring vigorously) and hand it over the shower rod to dry.  If I need it quickly I put a fan in the bathroom to blow  on it.  It dries pretty quckly that way.  I used to have the same problem and ruined several projects until I started doing this.  Now I preshrink all of my interfacing when I bring it home.  HTH. Susan