An introductory video tutorial on creating comparisons can be found here: https://www.orkg.org/orkg/add-comparison

Comparisons give an overview on the state-of-the-art for a particular research question. Thus, a comparison should address a particular research problem/question.

It might be challenging to determine the right properties for describing contributions to the particular research question. A guiding principle could be to represent the information researcher in the field would find relevant for comparing different works. Another approach could be to represent in the contribution description information, which is/would be contained in a well-written abstract. Typical candidates are usually: used methods, datasets, attained results etc.