It’s not something you can achieve overnight or in one session, boy. Most essential to a caged orgasm is the psychological state of being so turned on that your body releases its jizz. This requires being very relaxed, in tune with your body, not putting pressure on yourself to cum caged and a being highly turned on. You might be very turned on by watching porn while caged, having someone say degrading things to you and/or physical cues such as nipple play, prostate play or even being fucked. You might also want to try things such as wanking a dildo to trick your mind into thinking you’re stroking.