Please tell me how I can get my 4 month old shi-itzu puppy to let me know when she needs to go out to the loo, she goes outside when I take her but if I don't watch her like a hawk she goes on the kitchen floor, I need her to let me know when she wants to go out but have no idea how to achieve it!

Capri Sun - FamilyEducation.com (http://life.familyeducation.com/dogs/pets/45660.html) I'm not sure what to say so I found this xD the small advice I can give you is if you see that your dog has done a wee on the floor gently drag him/ her towards it and point at it then at him and lower your voice he might not be able to understand you but if you point and lower your voice he will understand it was wrong then drag him outside, leave him/her there for awhile while you clean up the wee make sure its fully gone so there is no oder from it so he won't be tempted to pee in that spot again. ^_^

(as bushg said my advice is proberly wrong xD that's what my mom does to my dog but she is a lot older then 4 months so I doe know lol sorry I couldn't help)

Letih your advice is contray to the link that you posted.
Dog's and puppies are not supposed to be punished or to be made to fill fear over having an accident.
In fact at 4 months of age the puppy does not have the muscle development to keep it from weeing at will. So dragging it to its accidents is only going to cause the puppy to be fearful of its owner.

In this link you will find some indepth information on how to train your puppy.
https://www.askmehelpdesk.com/dogs/information-articles-our-dogs-expert-labman-53153.html