Set a large bowl on top of a kitchen towel. This will pad the bowl while whisking.
Add the egg, lemon juice, mustard, and salt to a large bowl. Whisk until they are well combined.
1 egg yolk, 1 teaspoon dijon mustard, ¼ teaspoon sea salt, 1 to 2 teapoons lemon juice
Add a few drops of oil to the egg mixture and whisk to form an emulsion. Continue to whisk the oil in a drop at a time until you have about one-quarter of the oil whisked in. Add the oil slowly to avoid 'breaking the emulsion.'
½ cup canola oil
Once the emulsion is stable and begins to thicken...you know you're here when the mayo gets thicker and lighter in color. You can now add the oil in a little bit fast while continuting to whisk.