This time of year, I'm doing my 4.5 mile short route most of the time. I really like the three-seasons where most days I use my 16.5 mile long loop. Those are my favorite days. At the last branch I worked at, my long loop was 18.5 miles. So 19.5 is not really a problem.

You'll probably have to work up to 39 miles a day every day. It's doable, but you won't do it in the first week. Alternatives are intermodal--drive, bus or train for half the trip--or switching off--put the bike on the car and drive in, bike home. Next day bike in, drive home. Repeat.

It's helpful to be able to store stuff at work. Lockers are a godsend. I keep mine stocked with a couple of small towels, deodorant, lip balm, skin lotion (for when the sun comes out again in May or June), chamois lube and extra socks in case of rain. A canister of Gatorade powder is in there too.

Then on Mondays I load the panniers with the week's worth of work clothes, lunches and snacks. (And library books, which are an occupational hazard.) At the end of the week, (Thursdays for me) I use the panniers to haul home the laundry and more library books. Some people use cars to do this stocking instead. Others haul on a daily basis. It's up to you, but I like not feeling like a pack horse in the mid-week.

Few places have a shower, but every place has a men's room sink. Start with a fresh shower, deodorant, and clean kit at home, then a birdbath in the sink (that's what the towels are for) and refresh the deodorant.

I time my arrival for a least a half-hour before my start time. This gives me time to cool-down while having a recovery snack, then time to clean up. It also gives me a cushion in case of a flat or other mishap.

Failure to recover before starting work is asking for trouble. Plan on it, and execute the plan. I start just after lunch time, so I eat at work, using my lunch for both lunch and recovery food. The Gatorade helps in the warmer weather.

You'll also need a good bike, with decent tires and lights, and service it regularly and preemptively.

I also found jerseys and shorts I like for commuting, then bought six of each. I have clean kit every day with no mid-week laundering.