While a sailing vessel's preferred handling scenario is one involving wind and sails, most sailboats require an auxiliary form of propulsion to get them in and out of the slip. Whether this is an inboard or outboard, gasoline or diesel, there are some handling characteristics to become aware of as you back your pride and joy out of the slip and head for the great blue world lying beyond the confines of the marina. The key to tight-quarter maneuvering is planning in advance.
Before leaving the dock, assess the wind and current—and anticipate how they will affect your vessel. If you back up out of the slip with a following current and there are boats in the slips behind you, don't wait until you are right on top of them to start your turn out. Once you're sideway to the current, its force will become amplified and, if running sufficiently hard, you could end up pinned against your neighbor's pride and joy on the dock downstream of you. Conversely, if you back the boat against a strong current, give yourself enough space to turn the boat and allow for the current to set you. Not sure which way the current is going? Look at pilings. If they are wet a foot or so above the water, the current is flowing out, or ebbing. If they are dry, the current is coming in, or flooding. More than likely though, you'll be able to tell just by observing the water's surface—sticks, foam, seaweed and other miscellaneous flotsam will indicate the direction.
Everyone seems to have a different technique for backing out of the slip. The idea is to avoid dockside heroics. One way to do this is to position a line handler at the bow and stern of the boat. By running a line around a horn of the cleat and back to the bow, it's possible to guide the boat out of the slip. Once the boat is in reverse and has some way on—sufficient force through the water to keep steerage—a flick of the wrist fore and aft is all that is required to disconnect from the dock. Make sure that the line is wrapped around only one horn of the cleat, and not the bottom of the cleat. It's a slightly more involved rodeo-like line handling move to get the line off the bottom of the cleat, and the boat can start backing out while still attached, making for a messy exit. If an inboard is your auxiliary, here is where you're likely to come to terms with the force and direction that your vessel ‘walks' due to the rotation of the propeller. Depending on which way your prop rotates, your vessel will back to one side or the other. With an outboard, the same may be true, although it can usually be compensated by offsetting the motor slightly.
By now you also have ensured water is coming out of the back of the engine, there are no lines hanging over the side, and there's no other traffic that could cause potential problems. Maneuvering in some marinas can mean blind turns and visibility limited by large powerboats or other craft. Keep a sharp lookout.
Once past the confines of the marina, adhere to navigational markers and the traffic scheme. The preferred passing scenario is port to port. Stay clear off commercial traffic like tugs and ships, since many are constrained by their draft and need to stay within the confines of the channel. Bear in mind also that not only do these types of craft have right of way and are larger than the typical sailboat, but that they are less maneuverable and require a speed many times higher than a sailing craft to keep their steerage. If you encounter a crossing situation with another vessel that is too close for comfort, make corrective actions that are obvious to the other skipper. A series of small corrections can bring both vessels into closer and closer quarters. Large course corrections signal early intent.
When preparing to dock, allow crew members ample time to rig dock lines and fenders, even if it means having to circle back for more time. If a change of fenders or dock lines must be made from one side to another, the earlier crew members know about it, the better. Make the approach to the slip with enough way on to allow steerage. Keep an eye out for possible alternative landings should the need arise due to wind, current, or someone else being docked in your slip. Avoid barreling into the slip at a high speed, followed by a tachometer breaking blast of reverse, since this invites disaster at some point in the future. Jumping from the boat to the dock should also be discouraged because the risk of a twisted ankle, or worse—like falling between the boat and the dock—is not worth the risk of marring the hull. Finally, never get fingers, hands, toes, or anything else between a moving boat and the dock. The momentum of even a modest-sized sailboat is no match for tender body parts.
Assess which line will be necessary to break the momentum of the boat—usually the stern line, but sometimes the bow line if backing in. It's advisable to let the boat coast into the slip in neutral, followed by line handlers stepping off, the stern line breaking the boats momentum, and tying the boat to the dock. A short blast of reverse can also help. When the prop wash reaches midships along the hull, the boat has stopped. If short or single-handed, a line midships affixed to a cleat will also serve well.
Remember that the only secret of good helmsmanship is to know your boat, and this is something that only comes with experience.