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Four stimulus sets, need them to appear in random order for each participant

OS : Macbook using the psychopy builder, will be put online with pavlovia.
What are you trying to achieve?: I have four sets of stimuli, and I would like them to be presented randomly for each participant, e.g. participant 1 sees, instructions, stim set 1, instructions stim set 2, insutrction, stim set 3, instructions and then stim set 4, participant 2 sees stim set 2,3,4,1, with instructions inbetween etc. I’m not quite sure how to do this. I know how to randomize ALL stimuli in an excel sheet, this is not what I’m trying to achieve.
Any suggestions would be helpful. Do I put all 4 stimuli sets (pngs) in the same excel sheet and somehow tell psychopy to randomly select 0:9 and then do 24:32, then 9:16… or do I put each set in a separate excel sheet and somehow tell psychopy to randomly select one of the excel sheets after each set of instructions?

Thanks for you help!

You can do that using 4 excel condition files and two loops, one inside the other. The inner loop you set the number of repetition you want and the type of randomization, and in place of the condition file you place a variable (e.g. $mySet). In the outer loop you use a condition file with a column named mySet that contains the full name (don’t forget the extensions!) of your 4 excel condition files. Set the outer loop to random with one repetition and you are set.

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This worked and was very simple. Thanks so much!