I've lost count of the lucid dreams I wasted and dream goals left unaccomplished due to my inability to control particular aspects of my dreams.. The parts that I have the most trouble with are changing the scene and summoning people. For some reason, I can manipulate and change already existing objects just fine, very easily in fact.

After observing both my failed and successful attempts at summoning for example, I noticed there are two distinct 'mindsets' I had every time: when I would fail, there was this doubt in the back of my head, even if it was a really tiny doubt deep down, it would still cause me to fail, this distant feeling of "dammit, it might not work, watch it not work". When I would succeed, I had to adopt this mindset where I kind of had to, as weird as it sounds, I had to reject and block the logical part of my brain that said to me "that can't happen". And it had to be quick, that feeling is so damn transient, it's such a small window until the doubt leaks in and ruins it!

I read a bunch of fancy tricks you can do for dream control, but I've had both success and failures with both the 'bad' and the 'good' dream control techniques, the difference was the mindset I had when I used the techniques.
Is there any way to make that 'success' feeling accessible to you whenever you need it? Any sort of mental exercise or meditation or something? I'm so tired of 'wasting' LDs, and the most frustrating part is that I know it's my fault because the logical part of my brain refuses to stay away with its waking life logic and ruins all the fun.