IM injections in the hip should be given from the side, not the rear, to avoid hitting the sciatic nerve. There is an article on my website instructing how to give injections properly. Although some people give injections in the neck, I personally do not recommend this. I am always concerned about the possibility of hitting a blood vessel or artery. Injecting air into a vein will kill the animal.
Goats are dry climate, sparse vegetation animals.
If you raise goats in areas of extreme wetness or standing water, the fight against worms will be continual. I believe that the majority of worm infestation occurs because some producers do not adhere to a strict de-worming schedule and do not do routine fecal checks. And I believe that the cost of the de-worming products has a lot to do with this approach. However, it is very shortsighted. Losing a quality animal to worms is both a huge economic loss and a very slow death.