If you are new to steroids, you might want to start with glute shots. They are easy and its a big muscle. AAS tends to cause some pain, especially when you aren't used to taking it. Test cyp is a good compound to start with. I would rotate between glutes. I would inject with a 1.5in needle. If you want to try delts, you can try to rotate them in. They are an acceptable site. Just remember they are a smaller muscle and the oil doesnt have as much room, so inflammation can be worse. 

As for estrogen and gyno, adex dosing is individual. I would start at .5mg 2x wk. If you see yourself bloating badly, you can go as high as EOD. Rare people need ED. Adex can usually catch gyno before it happens if you pay attention to your body. If you start to feel any tenderness or itchiness, take more ASAP. If you really want to protect yourself, on this cycle you can also keep nolvadex on hand. If you feel any signs of gyno coming on, take a couple nolvadex asap and also increase your adex. Nolva will block the receptor while adex reduces estrogen production.