Step 1: What Is It?
The answer, my friend, has many answer but the best one, if you are in that situation, you will need some thing to boil your water! The easiest way to do this, if you have it avalible, is to create a cup of bamboo! You might be thinking, Pshhht, bamboo?!?!? Well, you shouldn't be. Bamboo(grass) is naturally sigmented with a usual thick outer shell, perfect for holding water.
Step 2: How to Make It(option 1)
How to make this cup? Easy, if you have a knife! If you do have a knife, you will first cut a slice on both sides of the bamboo, to try to limit the strain on you knife, because this is one of your most important tools you will help you survive. Once you have the two or three cuts around the Bamboo, it will break of with a small to medium ammount of pressure. As I said in the last step, bamboo is naturally sigmented, which you can fasion into a makeshift cup. With your knife, you can(optionally) add a small hole near the top so you can use a small(BUT STURDY) stick to lift it out of the fire.
Having no knife on the other hand makes it a little trickier. You will have to break the bamboo by hand, so you will want to locate a weak stalk and try to break it through pressure. After that, it would help if you could find some sort of sharp object(stone, ect.) and try to carve a section out of the bamboo, or at least weaken it to help you break it with your feet or hands. Fill with water, place in fire, use two sticks to remove from heat.
TIP: The more live bamboo is, the longer it takes to burn
TIP: Make tea by adding White Pine Needles(comment if you need discription) which are an ok source for vitamin C
Step 3: How to Make It(option 2)
The thing we will be using in this option is heavy duty tin foil, which can be used to make a cup, but will take many layers if you want it to stand up to the intence heat of a burning fire. The only down side to this method to this method is having the tinfoil on you during the situation, which is why it is a good idea to keep it in a survival kit.
TIP: Good idea in a Rural Survival Situation, like if you had been robbed of all of your important things in your house(UNLIKELY BUT POSSIBLE) and only have the basics left, with nowhere to obtain more of any item.
Step 4: How to Make It(option 3)
Step 5: Hope You Guys Enjoyed!
ALL METHODS CAN AND SHOULD BE ADAPTED BY YOU STANDARDS TO SUIT YOUR ENVIORMENT!