There's this dichotomy in hypnosis between being authoritarian and direct or being indirect and permissive. New hypnotists often want to know which is "better", and the answer is always "it depends". Happy with that answer? :p
Okay, enough with the "it depends" and "everyone is different" fluff. It's not a "red wine or white?" kind of preference. It's more of a scalpel or sword kind of thing. There really is a right choice - it just depends on the context and what you're trying to do. Behold! The criteria for choosing!
As a "hypnotist", I'm usually quite direct. As a "person", I'm much more indirect and permissive. If someone is coming to me to be hypnotized (or, for that matter, if I want to take control and blow someone's mind), it's just a waste of time to do anything else. Compare Ant Jaquin's cold induction of the barman to Nathan Thomas's arm levitation. There's a world of difference. I'd die of thirst before Nathan could get me a drink with that approach.
Being indirect and permissive is all about dodging resistance. If they're coming to you to be hypnotized, you already have something they want. Blow through that resistance. Direct suggestions hit harder. Instead of pussy footing around with "In a moment, you might notice one of your arms getting lighter. Maybe it'll be your right hand - that's right...or maybe it will be the one that's left that doesn't want to not start feeling light - that's right..." Just cut the shit and say "you feel your arm getting light". So what if they might say no? "Okay, now feel it getting light". What are they going to say? No? They came to you. If you know enough of what you're doing that you can give instructions that they can follow - then given enough pressure, you will never get stuck. If you know how to break suggestions into their components and know where attention needs to be directed, you can always be more specific and clear. So put on the pressure, cut the shit.
The upside of being direct and authoritative is that you can put the pressure on and quickly get intense effects. The downside is that it doesn't work when you don't have something to push them up against. They don't have to actually come to you, but you have to be able to force responses without them running away. If you can get them to commit to making it work, then go direct. In fact, that is my standard first move - get them to commit to making it work so I can go direct.
However, that's not always appropriate. There are times when you might want to influence people that would just run away if you said "hold on a moment, can I hack into your mind and just place things there?". And there are times when people aren't willing to take the one-down status position for a moment and follow your direct instructions. And also times when you have something you think they'd value, but they don't yet see it that way. And times when you're not sure if they really want to go with it - so give them the choice.
The only time I'm indirect is when conversational (though indirect and conversational are not synonymous - I'm often very direct in conversation)
A lot of indirect hypnotists think about fancy language patterns to use. If you find yourself in that unnatural mode of designing spells, you should double check yourself. I mean, there is some value in this for particular cases, but it should not be your go to. When I'm indirect, it's not because I'm pussy footing around. It's not because I'm trying to confuse and deceive people into giving my arguments more weight than they should. The point of being indirect isn't so you can be a slimy used car salesman and try to say things without sticking your neck out. Screw covert hypnosis.
The main point of being indirect is to qualify your suggestions. Sometimes unqualified suggestions are false so you can qualify it to more accurately represent your certainty. Or maybe the suggestion is too aggressive, so you qualify it to represent the social pressure you want to exert, or whatever it is.
For example, if you want someone to enjoy the taste of a food that they didn't like last time and you think they might like it more if they gave it a real shot, then try "you might notice that it's actually not bad when you focus on the pleasant aspects". But don't qualify with "you might notice" because "that makes it so that they aren't so critical when you feed their subconscious the suggestion". Qualify with "you might notice" because they might actually notice that it's not bad when they focus on the pleasant aspects.
Now that I think about it, there's a second qualifier there. "When you focus on the positive aspects". It might get you results just telling them they might like it - if that causes them to expect to like it and therefore focus on the positive aspects - but if you know it's about directing attention, and you know where to direct it, just do it directly: when you focus on the positive aspects. And with that qualification, your statement is more also likely to be true.
The magic comes from finding the right moves for them in enough precision to communicate effectively. Which obvious-once-stated truths are moving? Once you recognize what they should do and what kind of results you can expect, you can just like... tell them. Don't hold back, don't shoot yourself in the foot with lack of confidence. But don't work so hard on projecting confidence and coming up with sneaky spells that you come off as try hard. Just say it.
Say "you might notice" when they might notice. Or "you can" when they can. And "you should" when they should. And "I'd like you to" when you'd like them to. The effective qualifications just come out naturally.
So there's the difference. When you can secure commitment, secure commitment and go direct. Really. Cut the shit and just tell them what do do. And they'll do it for the same reasons they committed to doing it. When you can't, be as indirect and permissive as natural conversation dictates. If you're unsure about something, be confident in your degree of uncertainty. If it's not your place to do more than offer up your view, then just offer up your view. Woooooooo! The power of hypnosis!