There have been a lot of projects on here that involve fiberglassing of various components.  Here are a few suggestions that will make the job easier, and less messy.

To spread the resin.  Get a couple of four inch roller handles.  Buy a six pack of rollers from Home Depot for about seven bucks.  They are nine inches long, so you will cut them in half, giving you two four and a half inch rollers from each, or twelve rollers.

Get all your materials organized before catalyzing any resin.

Do not fiberglass in direct sunlight.  You won't be able to work fast enough, especially on warm to hot days.

Mix the resin in small batches using the least amount of catalyst recommended.  This will result in a slower cure time, allowing you to work at a comfortable pace.

Get some painting roller trays.  The narrow ones will handle your 4 1/2" roller. 

Get some latex gloves, or pvc if you have a latex allergy.  Get a gallon of acetone for cleanup.  It's about twenty bucks a gallon now.

Don't leave the cover off.  The stuff evaporates rapidly, as fast or faster than rubbing alchol.  It may be available in smaller sizes, for small projects.

If you do it in a shed, garage, or whatever, be sure to ventilate it.  The fumes can make you woozy.  If you can open doors or windows on opposite sides do so, and use a fan, either pedestal or window to keep those fumes from building up in your work area.

Gallon milk jugs are excellent for mixing the resin.  Pour a pint or so of resin into the milk jug, add the catalyst, put the cover on and shake the jug to mix the contents.  I swirl it with up to a half gallon of resin and it mixes in a few seconds.

If you can get the colored catalyst, I use red, for laminating do so.  You can tell when the resin and catalyst are thoroughly mixed.

Pour the prepared resin into the roller tray, and use the roller just like you would for painting.  You only want resin in the deepest part of the reservoir.  If your roller drips, get rid of some by rolling it on the sloped area of the tray.

Coat the parts to be fiberglassed then place the material, usually mat, onto them and roll them out, reloading the roller as needed.

The beauty of this method is that if you get too much resin in one area, you can pick it up with the roller and move it to another area where it's needed.

If you're careful, the resin will end up only where it's needed, not on your shoes, clothes or the floor.

If you're glassing something with corners, be sure to radius the corners.  Fiberglass does not like making sharp bends.  For inside corners, you can make a radiussed cove with a spreader that's cut to the shape you want.

If you do work with Bondo, use the catalyst sparingly.  It will kick in minutes.  If it starts to kick while you're working it, leave it alone until it does.  It's easy to sand.  If you try to spread it when it's kicking you'll end up with clumps and a mess.

The same goes for glassing.  If the material starts to kick, stop, and leave it alone.

When it's fully cured, use a belt or disc sander to even it out, then resume laminating.

When you've finished glassing, you will not have a smooth surface.  If it will show, and you plan to paint it, sand it with a power sander.

You don't need to get it smooth, just fairly even.  Then spread it with Bondo to fill any irregularities, sand when cured, prime and paint.

As with any project, preparation is the key.  Make sure you have all your materials handy.  Do any cutting of patterns before you start to laminate.  Take your time.  One of the advantages of fiberglass is that you can do it in several stages.

One more hint.  If you need to use several pieces, tear the edges, and overlap them.  This will feather the joints.  Using the milled edge is obvious, and produces a step on the surface.  Fiberglass does not sand easily, so you want to keep that to a minimum.

I hope some find this helpful.  I'll be glad to answer any questions you might have.

Great post, Rhino.

Want to add that using Marine Tex below water line for fiberglass chips is another great option. 

Awesome tips!

Great info Rhino.  Having never done it, I don't think I want to try it out for the first time on my bass boat.   :-/

I'm quite sure I'd screw something up and spend the rest of the day trying to kick myself in the head.

Maybe I'll go next door and see if my neighbor needs and fiber-glassing done on HIS boat... :

Great info Rhino. Having never done it, I don't think I want to try it out for the first time on my bass boat. :-/

I'm quite sure I'd screw something up and spend the rest of the day trying to kick myself in the head.

Maybe I'll go next door and see if my neighbor needs and fiber-glassing done on HIS boat... :

One other thing I should have mentioned.  If you are working around finished fiberglass, or anything else in the cockpit of a bass boat you can protect other surfaces by masking them off.

Get some of the heavier gauge polyethelene plastic film available at Home Depot, Lowes, etc., and a roll or two of the wide masking tape.

Tape the film in place.  Don't worry about being precise with the placement of the tape.  Close is good enough.  When you have that in place, then you can tape over the edges precisely where you need the tape.

If you want, you can reverse the order.  Tape to the protected edges first, then place and tape the plastic film.  It can be a pain trying to handle the film and tape, and trying to line it up perfectly.

If you need to follow curves with the tape, use narrower tape, 3/4".  The two and three inch widths do not follow curved contours very well.

There is another possibility to protect the wood.  Gluvit.  It is an epoxy product.  You apply it with a brush like paint.

Don't use fiberglass resin.  It will eventually crack and allow moisture into the wood.  Gluvit will seal the wood, bond well, and has enough flexibility to maintain watertight integrity.

http://www.westmarine.com/1/1/25246-gluvit-epoxy-waterproof-sealer-quart.html