Of course this is a common question and a easy problem to tackle...

Take your puppy out right after he's eaten. He will probably do both. Take him to the same place each time so he associates that place with doing his business. If you catch starting to pee inside, yell him "NO!" and take him outside right away. Don't scold him or he may become confused, but always praise him when he goes outside.

See I told you, simple!

Flat collar
Flat collars are commonly used in clicker training and other non-correction-based training, such as puppy kindergarten. They are also effective in training small dogs, however they tend to lift the dog off the ground when giving corrections while the dog is distracted or in high adrenal mode. They are typically made of nylon or leather, and fasten with a buckle or quick-release connection.

Slip collar
Slip collars (commonly called choke chain or check chains) are made of metal links or rolled material such as nylon or leather. A metal ring is at each end. Historically, slip collars have been used as a matter of course, mostly in North America and the UK. In the last few decades use of these collars has declined. Correctly used, the collar should make a quick clicking not zipping sound when quickly snapped and released to startle or get the attention of the dog and indicate to the handler that the technique was a swift jerk not a choke. The idea is not to strangle the dog, though this can happen if the collar is improperly used.

Martingale collar
Martingale collars (also called limited-slip collars) and are usually made of flat nylon with a smaller fixed-length section (made of either nylon or a short length of chain) that, when pulled on by the leash, shortens up tightening the collar around the dog's neck, to a limited extent. When properly fitted, martingales are looser than flat-buckle collars when not tightened, and less severely corrective than slip collars when tightened.

Prong collars
Prong collars (also called pinch collars) has the same design as the martingale collar but are made of metal links which have prongs on the inside of the collar. The collar is designed to inhibit forward movement and issue corrections by causing the dog temporary discomfort or pain. Proponents state that prong collars are gentler than slip collars. Sometimes rubber tips are fitted on the prongs to reduce damage to the fur and skin of the dog.

Shock collars
Shock collars (also known as E-collars) transmit a remote signal from a control device the handler operates to the collar. An electrical shock is transmitted by the handler remotely, at varying degrees of intensity, from varying distances depending on range frequency. It is also done automatically in the bark electronic collar to stop excessive barking, and invisible fence collar when the dog strays outside its boundary. Shock collars are widely accepted in some areas of the world and by dog obedience professionals. Shock collars are also banned in some countries, and some dog training associations, veterinary associations and kennel clubs condemn their use.