Vomiting is not a disease or disorder in itself; it is a clinical sign of some type of digestive disturbance or as a result of another disease or disorder. Occasional bouts of vomiting can be considered normal but if the vomiting persists and is accompanied by severe or bloody diarrhoea, lethargy, weakness, depression, pain or fever then this is a sign that something is seriously wrong and veterinary attention is required.  Vomiting can be caused by something the dog has eaten (e.g. rotten food), ingestion of toxins, adverse reactions to drugs or an allergic reaction to something in the environment.
The key method to adopt here is one of positive reinforcement. Firstly, you need to show your pup the area where it should do its business, and each time the pup toilets in the designated area, immediately reward with a treat or verbal praise. In order to prevent mistakes from happening, it is important to both diligently supervise your dog while it is indoors and take it frequently outdoors. This will speed the learning process and prevent any accidents from occurring in the house.
Keep your dog busy by prolonging his mealtime with a number of interactive toys such as Kongs, treatballs, or Bustercubes (treats can be easily pushed in but will engage your dog for hours trying to get them out). Also try hiding part of his meal around the yard to stimulate his natural foraging instincts. Treats and toys are available at the RSPCA online shop.
Puppy Roundworms can infect humans. To prevent this infection, puppies should be wormed regularly throughout their first year of life, and owners should be thorough with their own personal hygiene after having interacted with the dog. Tapeworms, Hookworms, and Whipworms can also infect dogs, and your veterinary surgeon can advise when to worm the dog. 
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