Buy the kit, not the pieces, the first time. Assembling your own set means discovering that the cuffs do not clip to the tether and the rope is the wrong length. A matched beginner set removes every one of those problems for less than buying the parts.
Cuffs before rope. Rope looks better and is genuinely more versatile, but it is a skill that takes real practice and it carries real risk if done badly. Cuffs give you the same restraint immediately, with a buckle you can undo in one second.
Check what it does to circulation. Anything restraining should take two fingers underneath. Numbness, tingling and color change all mean stop now, not soon. Never leave anyone restrained alone, not even briefly.
Impact play starts far lighter than you think. Fleshy areas only, meaning backside and thighs. Never the lower back over the kidneys, never joints, never the spine. Start at a quarter of the force that feels right and build from there.
Leather needs conditioning, silicone needs nothing. Leather cuffs and floggers age beautifully if you look after them and crack if you do not. Silicone and nylon are the low-maintenance choice, and they can be washed properly, which leather cannot.
Talk about it before, and talk about it after. The conversation beforehand is a safe word and hard limits. The one afterwards matters just as much and gets skipped far more often.