Passive voice is usually used to describe methodology because emphasis needs to be placed on the action rather than on the person who carried out the action. The use of passive voice has the effect of depersonalising the information, thus making the tone more academic and professional.
When forming passive voice of the simple past tense, you need to use “was/were” and the past participle of the verb.
Now, practise writing the Methodology section using the notes given. Make sure that you choose the appropriate verbs and use the correct tense and voice.