Although it gave me terrible translations, one very rough method I used at first with ut was to just ignore it was there and put the subjunctive verb in an infinitive.
So for chapter XXVII “Dominus imperat ut colonus accedat.” I would just translate it as “the master orders the farmer to approach.” Further down the page “Impero tibi ut mercedem solvas” I would roughly translate to “I order you to pay your rent.” This method doesn’t always work but it helps you understand the meaning. You’ll acquire a far greater understanding of the subjunctive the more you read.
Here’s some help I got for cum.
http://discourse.textkit.com/t/cum-and-the-use-of-the-subjunctive/7664/1
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