I’ve been trying to acclimate myself to metric. I always felt like the US was being kind of a dick by holding out for so long (well, us, Burma, and Liberia). And while I’ve heard people say, “Well, it’s too late for me, let the next generation learn it,” who will teach them if not us?
As for why the various metric measurements are better than British measurements, I won’t bother explaining in detail. Suffice to say, I think they are each wins, and I can elaborate if anyone cares.
Now, how to switch? Baby steps, mostly. Remember the advice the EU gave as they switched to the Euro: Try to get a natural feel for how much something is in the new system, without converting. Know in your gut how hot 14°C is, how it feels to walk 500m.
24 hour time is not really part of the metric system, but it’s along the same lines: simplification, standardization, and the rest of the world is using it happily.
Switching to 24 hour time is pretty easy. Just set your computer clock to 24 hour, and any digital clocks in your house that support it (including any digital watches). However, likely many clocks won’t support it (like microwave clocks, etc), and 24 hour analog clocks are not common. So you will have some hold-outs. But as you replace digital clocks, look to buy ones that support 24 hour time.
The mental conversion is pretty easy (just add/subtract 12). The goal is to know that you leave work by 17:00, you eat around 18:00, you get pretty tired by 22:00 (or at least I do :)), etc. To reduce confusion when verbally saying a time, say “17 hundred” rather than just “17” (as you might just say “5”).
This is a bit tricky. A kilometer is about 2/3rd of a mile. A meter is almost exactly a yard (i.e. 3 feet). And a centimeter is about 2/5th of an inch (i.e width of a thumbnail).
But it’s not easy to get a grasp for how far each of these measurements are in a day-to-day sense. I suggest setting your GPS device to display in meters. Memorize your height to centimeters (e.g. I’m about 188 cm or 1.88 m tall). Have Google Maps (or whatever) show directions in km.
If you use a treadmill, see if you can set it to metric. That will give you a real sense of how far a kilometer is.
Also a bit tricky. Soda is sold by liters. Note it. 1 oz is about 30 ml. A shot of whiskey is almost 50 ml. A cup is a bit less than 250 ml. A tall glass of water is about 350 ml.
Most packaging has both English and metric measurements on the labeling. If you get recipes from a web site, they often have the option to display ingredients in metric. Use it. As you shop, you’ll quickly get a feel for how many grams are in a can of peas or whatever.
When you go to the gym, many weight machines show both English and metric. Think “I’m going to push 5 kg” rather than “I’m going to push 10 lbs.”
Memorize your weight in kg. I’m roughly 68 kg. (See! Smaller numbers! You can tell people “I’m 80” and just don’t elaborate.)
A paperclip is 1 g. An apple is about 150 g. An ultimate disc is 175 g. A newborn baby is about 3.5 kg. And remember, the camera adds 4.5 kg.
Every 10°F is about 5°C. And of course 0°C is freezing (or 32°F).
So 0°C is literally freezing (32°C). 5°C is cold (40°F). 10°C is cool (50°F). 15°C is warm (60°F). 20°C is hot (70°F).
Again, you can usually set your computer (or whatever site/device you check) to tell you the weather in Celsius. As you check that daily and go outside, you’ll get a feel for it. If you do this, don’t make the mistake of also checking the temperature in Fahrenheit (so you’ll “know what the temperature really is”). You’ll just end up thinking of the weather in terms of the more familiar measurement. Your goal is not to convert, but to know.