Mix the ingredients
Take a jar and place one cup of all purpose flour in it. Pour one-half a cup of water into the jar and seal its lid thoroughly. Now, shake it until the water and flour mix up completely, forming a thick sticky mixture.
Remove the lid of the jar and stir the mixture with a fork or spoon in order to make sure that both of the ingredients are finely mixed and all lumps are removes. Pour your glue into an empty glue bottle and seal the cap thoroughly.
Note: make sure that the mixture is neither to watery neither to thick.
Test your homemade glue
Your homemade glue is ready and now it is the time to test it. Take two medium pieces of a paper or newspaper and apply a thin layer of your homemade glue to them. Stick them together and set aside to dry.
Pull apart the two pieces of paper
Get back to the pieces of paper once they are dry and check it out by trying to pull apart the two sticked pieces of paper.
You will find the two pieces of paper tightly attached with each other. Why is it so? It is simple; the ratio of water in the glue evaporates into the air, making the glue harden. Same is the rule applied to the store-bought glue.