- Get a can of paint, some glazing liquid and practice - practice - 
practice before you get onto the walls.    Better yet if you have 
actual walls that you can practice on go for it - like in a garage. 

- Keep in mind that decorative painting is closer to an art than a 
science - which means some of the most impressive results can be 
achieved not through strict adherence to a formula but through exper-
imentation and improvisation.  Don’t be afraid to experiment until you 
find what you like and feel comfortable doing.  

- Doing up many sample boards may save you some headaches later on.  
It's much more fun to get going on the walls but take your time and
get comfortable with the procedure first.

- Don’t skimp on wall preparation.  If there are holes, fill them and 
sand making the surface as smooth as possible.  Then prime those spots
and paint your base color.

- Get everything in the room ready before you pour your paint into the 
tray.  Mask all trim, windows, adjoining walls and ceiling.  Money 
spent on masking tape will be better than trying to remove paint from 
these areas after you are finished.  Takes as long to prepare a room 
as it does to paint.  Put lots of drop cloths down and have paper 
toweling and old rags handy.

- Start in the left corner of a wall - if you are right handed and 
right corner if you are left handed.

- If you aren't sure what your old painted surfaces are - oil or latex 
here's a handy way to tell.  Take a Q-tip and wet it with finger nail
polish.  Rub it onto the wall and if some paint comes off onto the Q
tip, the walls are latex.  If nothing comes off, it's oil.

- Since glazing consists of layering different translucent colors over 
a base coat, you should choose colors that are related or in the same 
family to achieve the best results. 

- From a color chip you would usually choose a light color for your 
base coat.  Your glaze color should be 2 - 3 shades deeper.  Pick a 
deeper color of paint than you desire since it will end up 1-2 shades 
lighter once mixed with glazing liquid.

-Most reputable paint stores will mix paint to match any color that 
you have in mind.  Take a piece of fabric or picture or whatever with 
you when you get the paint so they can match exactly.  If you will be
mixing the paint with glazing liquid, remember it will lighten 
somewhat.

-What I quite often will do before I go buy a can of paint is mix up
some acrylic craft paints and experiment with different combinations 
to see if what I have in mind will actually work.  When I'm sure, it
is the color I want, then I go to the paint store and have them match
my sample card.  This has saved me many dollars over the years.

- When doing negative techniques, make sure your walls are painted in 
a satin or low sheen - not flat.  A flat paint is too porous and sucks 
up the paint so it dries too quickly.

- You can paint oil over latex but not latex over oil.  Same applies 
to any of the painted finishes.

- For negative techniques, leave a wet edge of unworked glaze 
at the end of each section to allow blending of the next area.  Work 
quickly - you have about 15-20 minutes before oil glaze becomes tacky.
If you have a helper, make sure the same person who starts a technique
does the complete job as every person has their own signature (style, 
pressure etc.).

- When ragging off, make sure you have an adequate supply of the same 
kind of rags.

- For sponging, the color you apply last will be the most predominant.

- Change the angle of sponges or rags often so the pattern is not 
repeated.

- Stand back and inspect your work from time to time to insure you are 
using the same pressure and technique.  

- For corners, cut a small piece of sponge or use a small bristle 
brush to stipple into them.

- NOTE:  When finished ragging with oil glaze, drape the rags over a 
rail or lay out in a well ventilated area until dry.  Then dispose of 
in an approved hazardous waste facility.  If you bunch these soaked 
rags up and put them into a garbage bag, they may ignite.

- Wash brushes and sponges as soon as possible in appropriate cleaner 
to prevent hardening of paint.

- If you do have brushes with hardened paint, I've found 'Goop' to be
an excellent product to soften this and then they can be cleaned.  Put
Goop in a metal container as it will melt plastic.  To soften acrylic 
paint, rubbing alcohol is very effective to soften it.