Hi kitkat. I used hypno for bith DC, here's my experience.
DD1 - listened to the cds in the bath in early stages, kept me really relaxed, used the breathing etc, was feeling good, transferred to MLU at 4cm and to be honest i think that's where i lost a lot of focus and never really got it back, i also struggled to successfully use visualisation and i don't think i'm a visual person. I used the pool and gas and air and got through it ok but i think i "let the fear in" if that makes sense.
DD2 - had homebirth last friday. Succeeded much better with the hypno. Partly because i wasn't scared of labour as knew i could do it (so not much help to you sorry). I decided nit to bother with visualisation and just focused on the breathing techniques. They do work if you try and make yourself stay focused. The benefit of hindsight looking back at DD1s birth is that i knew that each contraction does pass and there is a rest between each one. With DD1 i got anxious and stayed anxious between surges which made it all much harder work.
So really really focus on breathing through each surge, and either do visualisations if they work for you, or i just kept repeating the mantra in my head that this one will pass and it does. Then between surges really try and relax and take the chance to "regroup". I found my DH's support between surges invalusble, i'd prepped him to remind me to calm my breathing, relax my jaw (really does help).
Also keep focused on the end result, if i was sruggling DH would remind me it was bringing baby closer, and after a surge he'd hold me and tell me that was one less surge i'd have to do. Simple things that really helped. With my first labour DH was as overwhelmed as me, second time around i said what i needed from him.
Sorry the above is ramble, hope there's something useful in there. As you can tell i'm not a pure hypnobirther, as in i mean hypno didn't make it pain free for me, but it really does help.
If i could go back and speak to myself in labour with DD1 i'd tell myself to have confidence and stay focused. I did with DD2 and it was an empowering experience.
Ooo see how rambly/sentimental i am, can you tell ihave just had a baby?!:-)