It takes a lot of skill to do a nice plaster job. I have a close friend who is a master at it but it has taken many years of practice.
My suggestion would be to attach drywall to the brick then tape and mud the joints. This takes less skill for a DIY'r and is easier to undo in future.
I'm assuming you are just going to paint after, but if it's tile you are installing, the method should be different.
For tile: Instead of drywall use cement backer board, then thinset and tile to your hearts content following intructions provided by the supplier. For heavy tile you may need to support the tile against the wall till set.
If you want to plaster, you may not be happy with the results if it's a smooth surface you want. If you do, get some ready made plaster at a home improvement center. Get a trowel, narrow and about a foot long. Depending on the porosity of the brick (course or smooth) start with a thin scratch coat. If it's smooth and tight you may have to install lath. Dampen the brick before starting so it doesn't suck the water out of the plaster too quickly.
Before this first coat is dry run a damp brush over it to score the surface. This will create the bond for the final coat which will be thicker about 1/4". When dry you can sand it to improve the surface. A trouble light will help with the imperfections.
To get a perfectly straight and smooth surface takes a lot of skill. If this is really what you want, I would do the drywall method. You can use some nice trim boards at the edges and corners.
Have fun!
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Bart Blainey, B.E.R.
Consultant/Journeyman Carpenter
Building Envelope Specialist
Master Renovator
provip@prodeck.org
http://www.prodeck.org
Barton Blainey (provip) specifically assumes no legal liability or responsibility for the accuracy, completeness or usefulness of any information or process disclosed. The above further expressly advises that any use of or reliance upon the information and or opinion disclosed is at your risk .
_________________________
Bart Blainey, B.E.R.
Consultant/Journeyman Carpenter
Building Envelope Specialist
Master Renovator
provip@prodeck.org
http://www.prodeck.orgBarton Blainey (provip) specifically assumes no legal liability or responsibility for the accuracy, completeness or usefulness of any information or process disclosed. The above further expressly advises that any use of or reliance upon the information and or opinion disclosed is at your risk .