you need a DIY plumbing book
you can pick up “how to do” leaflets at..
B&Q
Do it all
Selco
Wicks
they are free and most helpful
good luck
Home Design Alternatives
The Complete Guide to Bathrooms
A friend of mine picked this up at Lowe’s and tells me his bathroom came out great(he had no talent for construction that I knew of). He replaced the fixtures(tub, toilet and sink), vanity, redid the walls and floor. If he could do it anyone can! I couldn’t help living 2500 miles away.