happyheart has a (needlessly long) video on YouTube about how to do 3x3+4bmm triples. This should give you an idea of how you're supposed to turn and stuff. Then you could try 3x3+4bmm triples without coords.
After that, you should practice 3bmm triples (
this is just a random one I found on YouTube). Remember to be aware of your facing because x and z facings are pretty different. Once you can do 3bmm triples, you probably have them down.
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Of course, you could skip all of that and just use coords.