Determine the main question in your essay you want to answer. Take the question and turn it into a positive statement indicating a relationship. For example, if the essay is about evaporation, make the statement "The sun causes the water to evaporate." This method is appropriate for correlation studies.
Write a statement that claims there is a difference between two things. For example, "The plant given one cup of water grows faster than the plant given two cups of water." This can be used as an alternative to the method for the correlation study and would apply to experiment studies.
Write a non-directional alternative hypothesis by stating that the findings are already concluded. For example, "The moon causes the ocean tides." There is no direction from the statement.
Write a directional alternative hypothesis by stating that the paper will prove the statement. For example, "The moon will cause the ocean tides." The use of the word "will" gives the statement direction.
Write a null hypothesis, which is related to an alternative hypothesis, by stating there is no relationship between the variables. For example, "The extra cup of water added to the plant makes no difference on the rate of its growth."