This is not C Ranger specific, but for any boat.
If you are launching off the trailer, be sure that all drain plugs are in place and secured. I would close thru hulls, and then open them when coming aboard before starting engine or genset.
Check the bilge for water, fuel or oil. Check thru hulls to be sure that they work and are in proper position (open sea water intake for the engine for example).
Check engine oil--level, and for water (Milky appearance). Check transmission and generator oil each time before start. Check fuel filters for water in water separator and to be sure that there is no air in the filter or fuel lines.
Check all instruments: depth sounder, chart plotter radar and radio for proper functioning. I do not believe in "Radio Checks" other than initial installation. I do occasionally check output and SWR with antenna analyzer--there are farily simple ones for about $50. Radio checks can be done by talking with other boats on channels other than 16.
Check to see that all fire extinguishers are in place and properly filled. Check horn for sound--(a little beep will do). Check life jackets, be sure that everyone aboard knows where they are, and if children are aboard that they have the life jacket on. (I would like to see at least whistle's on the life jackets and a strobe/flash light by ACR is also desirable.
Be sure that all flares and signals are in date, and in an appropiate place. Let the crew know where they are, along with fire extinguishers and life jackets.
Check your navigation lights to be sure that they are working and legal.
Check the First Aid kit to be sure it is intact and all know its location.
Check to be sure you have the no oil discharge plaque and garbage disposal plaque aboard.
When starting the engine and generator, look for cooling water. Visually check the engine, looking for fuel water or oil leaks. I like an IR therometer to check the transmission and engine block for hot spots. Check the battery voltage before and after starting the engine.
If you have the thrusters, check each one, in each direction--just a little spirt.
Check the Carbon monoxide detectors for fresh batteries and readings.
If you have propane appliances, be sure that the gas is shut off at the tank.
I also check to be sure that the windlass breaker is OFF--turn it on only when you want to use the windlass--you don't want it accidently activated.
Have passengers sit only in appropiate seats--not with extremities overboard or on the bow..
Before you venture out on the water, do take at least a coast guard aux course--better yet to take a Power Squadron series, including plotting and navigation.
If you have rigging which is folded or moved in trailering, check to be sure it is in place and secured.
When you are ready to leave the dock, be sure that power cords are unpluged. First turn off the breaker on the pannel and the dock before disconnecting the cords. Cast off the lines and be sure that fenders are stowed as soon as you clear the dock.
Consider filing a "Float Plan"--http://www.usps.org/o_stuff/fp_form.html
Or:
www.boatus.com/seaworthy/floatplan.asp (Click on the PDF link for the actual plan to leave with a friend.
Buy Chapman's Piloting and Seamanship. This is the "Bible". There is a shortened version--Chapman's Practical Boat handling.
Charles T Low "Boat Docking" is an excellent book.
Good boating--check the weather before you go out, and keep an eye on it!
You may want to take experienced boaters with you until you have some experience. The Ranger 25 is a great boat, but it is still a 25 footer and has limitations, especially in the bay and potato patch!
