Profiles
A profile is a series of target steps to be achieved on takeoff or landing, designed to give you the best chance in an emergency. For example, with a TwinStar in a clear area, you would go up to 6 feet, then nose forward to 10 feet and 30 knots, (CDP) accelerate to 40 kts (VTOSS) up to 550 feet, level out and accelerate to 55 kts (VY):

In practice, with both engines performing normally, you would accelerate as quickly as possible through CDP and climb away as you would with a single – only if an engine fails would you decelerate to VTOSS, or Takeoff Safety Speed (the equivalent to V2 in a plane, for the best angle of climb, then adopt VY at the prescribed height, for the best rate of climb.
The CDP is the only point where you have a choice of action – before then, you reject. Afterwards, you carry on. The LDP is a similar point for landing, where the idea is to hit a speed and height combination from where you can make an approach that will allow you to land safely (most people get to one first, then creep up on the other).

There can be many variations on the Cat A theme:
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Airfield, or Clear Area, with distances around 1000-1500 feet to play with, accelerating to where you can climb even at max weight, usually close to VY.

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Reduced Field Length, climbing vertically or even backwards, to land in a much smaller area if you have to, say 300-500 feet long, usually at about 85-90% max weight.

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Vertical, which speaks for itself, but you may have the option of a dip below heliport height or not (i.e. at ground level). The former allows 90% max wt, the latter around 80%

Class 1 helipad take-off procedures involve climbing vertically at first, then going upwards and backwards to a predetermined height (the Critical Decision Point, or CDP) before going forward (actually, ICAO now call it the Takeoff Decision Point, or TDP). This could be up to 150 or 200 feet above the helipad, after going vertically to about 50 feet first (if you've got the power on a hot day!). For the TwinStar, you start going backwards from about 15 feet, at around 200 feet per minute, keeping the helipad in sight, and at TDP (90 feet) select max power and 10° nose down at the same time, so your tail doesn't hit anything.
In theory, having moved backwards, you still have the take-off spot in sight and it's therefore available for landing. At CDP (or TDP), if you elect to carry on to forward flight, you should be able to clear the landing spot during the steep dive you have to make to achieve flying speed, which is why the CDP is about 40 feet high. Once you're happy about the power, gently accelerate level, to VY.
All this is not without its critics, though, since prolonged hovering at high engine power is not necessarily good engine handling. Not only that, it may be impractical on an oil rig if there are accommodation blocks and cranes around.
Unofficially, therefore (from a rig anyway), one school of thought suggests a level acceleration to best rate of climb speed, then going up to a safe altitude, whereas others advocate getting to best angle of climb speed, climbing to a safe height and then accelerating to best rate of climb. The first is supposed to keep you in the H/V curve less, but the second gets you higher sooner, so you lessen the chances of hitting the water if an engine fails, especially if the deck is only 50 feet high (most major platforms are 100 feet off the water).