As a former microbiologist, here's my take on sterile technique. Creating a completely sterile environment at home is difficult, but there are a few easy things you can do to minimize contamination.
tldr; turn off your HVAC, work in the loo
In greater detail:
1. Use sterile equipment. I mean, duh, your filters and syringes and vials are definitely going to be touching research products. So buy them sterile, use them once, and throw them away.
2. Work in a 'still air' environment. In the olden days of microbiology, it was common to work in 'still rooms' instead of HEPA-filtered clean rooms. These were basically glorified closets, with no air flow. You would just walk in, sit down quietly for 2 minutes without moving so that everything in the air had time to settle, then begin your work. Simply turning off your HVAC gets you closer to these conditions, and if you can find a small space with no air flow, so much the better.
3. Avoid spaces with lots of dust sources. So, while a 'glorified closet' might be a great space to create a still air environment, an actual closet with lots of sweaters above your workspace, and old dusty boxes, is probably not so great.
4. Wash your hands. I mean, actually, with proper technique this shouldn't matter, since your hands should never be touching anything which needs to remain sterile (vial stopper, needle, etc.). And germs can't jump, so they're not going to get onto your equipment without direct contact. But it's easy to do. So sure, go ahead and wash your hands.
5. Clean your surfaces. This one is really pretty far down on the list, tbh. Again, germs can't jump. It's easy, though, and a good way to kill time while you wait for the air to settle in your closet. So go ahead and give surfaces a wipe down with alcohol, or even just water to clear away the dust.
So what does this all mean? You should probably work in your bathroom! As long as you can turn off the airflow, it's a likely a nice small space with very little dust. You definitely don't want poo on your equipment, but nothing is gonna jump from the toilet to your workspace by the sink. So with a little bit of proper technique, this is probably the easiest place to quickly create a mostly-sterile-ish environment.
