If, however, they are not responsive, they will swim away, or turn back upright. Trying to restrain them will only break their trust in you, and could cause you serious injury. Pat them, stroke them and talk to them lovingly, but do not try anything else. It is best, anyway, to let the dolphin tell you when they are ready. It is far more pleasant, and more fulfilling anyway.
Aquariums are a bad choice, for many reasons.
Best thing sometimes is to find a beach or a cove that the dolphins frequent. Gaining their trust takes time, and you need to visit frequently. This is impossible for some people, I understand, but it is the best way. Sometimes you just need to be in the right place at the right time. I have been extremely lucky on two occasions with wild dolphins, and my current mate is a dolphin who lives in the harbour of my resident city.