Step 1: Transfer your voice memos to your computer, following the instructions here: https://www.howtogeek.com/289811/how-to-transfer-voice-memos-from-your-iphone-to-your-pc-or-mac/
Step 2: Open Transcribe, and click on "transcriptions", then click on "New Automatic Transcription".
Step 3: Select the voice memo files you downloaded to your computer in Step 1.
Step 4: Click on Upload, and that's it.
You'll receive your transcript in about half the time as the length of your voice memo.
Once you receive the transcript link via email, you can then edit it by clicking on the "Edit transcript" button on the right pane.