This sounds like an awesome challenge and a great way to level up your teaching skills! I'm always happy to talk more about various methods, but here's a short list of some of my "go to" favorites:
Backwards Planning
Determine what you want this person to know (content) and be able to do (skills) at the end of your time together. From there, breakdown the skills and content into their smaller component parts until you get to what seems like a reasonable base unit of knowledge/skill.
I tend to backwards plan for a given amount of time (an overall vision for the entire learning period - usually months), and then backwards plan into increasingly smaller units - generally down to two or three objectives within an hour-long session.
Vanderbilt has a good overall explanation, as well as templates.
If you're really interested, you can invest in the "Understanding by Design" texts as well.
Baseline Assessment (informal)
Use probing questions to figure out what the person already knows. This is an area where empathy goes a long way - you want the learner to feel supported, and not awful for things that they don't know. I try to develop open-ended questions that can get at some of this - so for example, instead of "do you know Excel?" I would ask something like "tell me about a project that you've done in Excel." This will help you get at some of the underlying areas of knowledge - as well as assess gaps in knowledge.
Checks for Understanding
Related to the above, checking in regularly to see if someone understands content/skills can help facilitate learning. Try to avoid yes/no questions like "does this make sense?" in favor of open-ended questions like "what questions do you have?"
There are a lot of great resources on developing question-asking skills. The University of Chicago has a great summary.
I, We, You
This is hands-down one of my favorite ways to teach - essentially it's "I do, we do, you do," which guides the learner from direct instruction to guided practice to independent practice. For example:
Direct Instruction
- Show them how to install and load a package in R, while talking through what you're doing.
Guided Practice
- Work through installing and loading a package in R, but ask them to provide guidance. You could say something like "OK, we've typed 'install.packages' - what's next?"
- Then do it again where you're typing, and they're giving you each step and telling you what to type
Independent Practice
- Then hand over the keyboard and have them do it on their own, while you provide guidance as needed
(I/We/You is covered pretty thoroughly in Doug Lemov's Teach Like a Champion 2.0)
Get comfortable with wait time
We have a tendency to want to fill the space between asking a question and getting an answer, but when you ask a question, people need time to think and process. It's OK to wait five or six seconds while they think about it, before providing guidance in answering the question.