Constructions are always pairings of form and meaning, but as with many things the devil is in the details. This lecture will show you how form-meaning pairs can be represented and give you an idea of the the main representational variants that you will come across in the literature.
Lecture notes available at Academia.edu:
https://www.academia.edu/44483409/Construction_Grammar_Week_2_How_to_represent_constructions
Further reading:
Hoffmann, Thomas. 2022. Construction Grammar: The Structure of English. (Cambridge Textbooks in Linguistics.) Cambridge: Cambridge University Press.
https://www.cambridge.org/highereducation/books/construction-grammar/D0577C9957038E384A2A1F04E6A73B7E#overview