Prepare yourself for rain
You need shelter. You don´t want do carry a lot.

The bivi-bag
The best solution is to carry a bivy-bag or bivouac-sack. I had one already, but you can also sew one easy. Look at MYOG sites, or try this one: http://www.backpacking-lite.co.uk/diy/make-your-own-bivy-bag.html

Some outdoor-lovers may know a Biwak-Sack or Bivouac-sack for the others... wikipedia :)
http://en.wikipedia.org/wiki/Bivouac_sack

condensed water and no good air
And when you have one, you may also have the problem with condensed water inside the sack. As the Sack is an emergency-solution, I don´t want to have a luxurious tent. Because I love to sleep outside under the stars and not in a tent, I just wanted to make my Bivouac-sack a little more comfortable without getting heavy. So it is still an emergency solution and you can make it with just a few more things. It is also flexible, so you can arrange optimally with your given surrounding.

Step 1: The Plan

My problem was to get some space between my sleeping-bag and my bivouac-sack. So I want to make it tent-like. I did not want to destroy the fabric, that´s why I realized another solution with clamps. We can keep it simple and flexible.

what we need
You need your walking stick, piece of rope, tent pegs, two different clamps and loops. Putting it all together you have a nice and small sleeping solution and a good shelter.

Step 2: Making the Connection Component

Having a sack, a walking-stick, some rope and tent pegs, you just need the most important thing... the connection between your tent and the tent pegs. I first tried to glue some loops on the fabric, but it turned out to be impossible, because of the fabric of my bivak-sack (it has silicone). They felt off like nothing, but if you make it out of another fabric, tell me to post my pictures making the mounting with rope and old jeans-fabric. Anyway, here the solution with clamps, loops and clips, working pretty well on any kind of fabric:

make a rope-ring

To make the ring out of a thick rope, you can ask the staff in the shop you buy it, to let you melt and put it together with their hot melting-cutter there. They usually have one to melt the rope, otherwise you can use a lighter. Work fast!

-Melt the ends of a ~15cm long piece and push them fast together before they start drying. Than start to fix the contact point and make a soft blending, as you see in the pictures. That makes your loops more robust.

The other part is a clamp you can buy everywhere, but you can also use another clamp. I choosed mine, because I could get them easy in the paper-store. They also have a maximum force and they will open themselves. That was usefull for me as I wanted them to open by themself, to not make wholes into the fabric, protecting me from the water.

the thickness of your rope should be smaller than the space between your clamp

Notice that the clamp and the thickness of your loops should work perfectly together, so that the force needed to open the connection is not too soft. The clamp is inside the tent, the ring holds it outside.

As it is hard to understand, I made a small video. In this video you can see how the components work:

Klemmösen... | vidup.de: Videos hochladen kostenlos ohne Anmeldung!

http://www.vidup.de/v/kz26y/

Step 3:

Now are done with the flexible part. The other clip-thing you see on the photos is easier to buy.

Where to attach it
It is good to leave it at the same place on your bivouac-sack, as a non flexible part. You should place them where you have more force and you don´t want to open them at all. For example at the corner points (with some rope and tent pegs) and at the position you want to attach the walking stick. For me it was perfect to have 9 flexible and 3 of buyed parts.

Step 4: Go Out!!

that´s it

It´s easy to get a better shelter at rainy days and making a cheap superlight-emergency tent!! :)
With my bivibag I reached about 450gr. that´s really good.
Now I love my bivi-bag again and I use it as an emergency tent.