3] Shaving is a comforting thing. It is normal to be nervous when shaving with a straight razor the first time. Don’t worry. If the proper measures are taken one will not cut one’s face off. Quite the contrary, one will get a glorious shave and will feel euphoric afterwards.
The common straight razor is a friction folder, so there is nothing holding blade or handle into position but one’s hand. Hold your razor in whatever way is easiest for you. There is no right or wrong way. However, there are some methods that have proven themselves over centuries of time and keep good control of the handle to keep it from flopping around.
These pictures are from the document, Traditional SR Shaving Instructions for Beginners available as a free download on the internet.

Three fingers on the tang/shank, one on the tang hook, with the handle pointed upwards between the ring and little fingers. The thumb is under the tang/shank pinching it.

Two fingers on the tang/shank and one on the tang hook. The thumb is under the shank/tang in a pinch hold. The handle points up between the middle and ring fingers.

One finger on the tang, the handle pointing up between the pointer and middle finger. The middle finger rests on the tang hook. The thumb is in a pinch hold.
For some types of strokes one may want the handle pointing downwards, but the idea is the same, to maintain control of the blade and the handle. Hold the razor in whichever manner is the most comfortable, but don’t be afraid to experiment. Change up as you need to do so.

For some strokes, such as against the grain going South to North, holding the razor like a Kamisori is liked by some. The fingers and thumb pinch hold on the sides of the tang.
Whatever the method, always hold the tang, also called the shank, and not the handle, or the razor blade will flop and cut the skin.
Some people recommend using both hands, right and left, when shaving. Other people use only their dominant hand to shave. Either is fine and neither is necessarily superior to the other. Using two hands makes some types of strokes easier, but using only the dominant hand makes others easier. It is one’s own choice.
Always start the shave in the same place to develop muscle memory. Most commonly, this will be on one side of the face under the sideburn or even with the top of the ear, depending on hair style. Lay the blade FLAT on one’s face and then raise the spine 1 to 1 ½ spine widths off of the skin. This will be about 15° to 20°. This is different from the 30° required for a safety razor. A straight razor cuts best and smoother from these angles.
Make a short stroke about a half inch/1.27cm long, and then another at the end of that stroke. Do not put pressure, only using the weight of the razor. The blade, if properly honed, will cut easily and it alone should be enough. Don’t hold it so lightly that the razor comes off of the face or skips. It should remain in contact with the skin throughout the shave stroke. However, light pressure and smooth strokes will result in a close, smooth shave.