Having done an US elective while a student and now helping to organize one as a senior resident, here are some thoughts:
1. a readable text (not too long or even just some excerpts on basic concepts and EM oriented scans)
2. a couple of 1 on 1 sessions to start...instructors should know the machine inside out: how to scan, switch probes, record, export to USB; then go through all the basics scans a few times and what to look for; e.g. RUQ and measuring CBD thickness or transvag while measuring FHR using M-mode
3. solo sessions and method of reviewing studies...it's 2009 and all the new machines take USB or some type of flash drive; maybe try digital reports if you have a long-term goal of creating an efficient review process; most places still use a form stapled to the fax paper print-outs...pick your poison (bumpty frontier vs. old tech)
4. organize resources into a digital format...a basic website with links to the machine manuals, recommended texts, documentation forms vs. digital documentation, blog element to add notes about quirks at your institutions (e.g. where the sterile probe covers are located)
5. the more you invest in 4, the less time you'll spend repeating yourself