Below are several general points I consider to be most helpful. They include one's attitude when trying to learn something new or in trying to reach a particular milestone along the painting journey....whatever your goal might be.
Probably one of the most important pieces of advice anyone could share: No matter what your goal may be, BELIEVE IN YOURSELF and THINK POSITIVE!
Learn to crawl or walk before you run. Don't expect a masterpiece right away or even every time you sit down to paint later after you've learned to "run."
Re-discover the child within. Think about a child when they decide to paint or draw. They jump right in...no hesitation. They know no rules but instead are driven by the creative nature we all possess. When complete, they normally display this huge grin and maybe even a giggle as they proudly present their masterpiece. Something precious even if not perfect (whatever that might be) because it was made by their hand and came from within.
RELAX and ENJOY what you are doing......even if it's only sloshing paint on to paper.
Practice, practice and do it again. Oh, and let's not forget another important point - PRACTICE. It's the repetitive process (as with most things in life we need or wish to learn) that helps us reach our goals.
Do not, and I repeat DO NOT BE AFRAID TO MAKE A MISTAKE. And even more importantly, DO NOT view those mistakes as failures. Those mistakes are not failures but instead extremely valuable lessons. You learn from your mistakes so have fun and feel proud of making them. The more mistakes you make, the more you learn; and the more you learn, the greater knowledge and experience in ability you will have gained.
Learn your basic rules, which in reality are only guidelines; however, don't be stifled by them. Art is subjective and one's likes or dislikes are based on one's opinion and sometimes mood at a given moment. And we all know opinions and moods can change like the wind (well for most people, that is).
Set yourself free and allow creativity to guide you rather than rigid rules and guidelines. Don't be afraid to experiment.
When critiqued by others, only take in what is relative and important to YOU and file away or discard that information that is not. Art IS subjective. Remember that the painting you are sharing is YOUR painting. When you go changing a painting just to please everyone else based on their own perspectives or preferences, that painting loses a part of you and starts becoming their painting. ("Thank you egeorge for that one.......one of the best pieces of advice anyone could share with another!!!!")
Don't be afraid to copy others' work.........even the great masters copied from one another. BUT REMEMBER, never and I repeat NEVER try to pass off someone else's work as your own. You wouldn't appreciate it if someone did that to you. It's best to obtain written permission but at the very least, give the originating artist the credit due when sharing with others. ABSOLUTELY DO NOT EVER sell a painting you did by copying. You could get yourself into some serious trouble.
This warrants being mentioned again.............Research and understand Copyright pertaining to painting from other artists' examples, tutorials, workshops, photos, magazine illustrations, calendars, greeting cards, etc. before EVER ATTEMPTING TO SELL or take credit for a painting you've completed. Your best and safest bet is to paint what you experience or from photos you personally take.
Don't fall into the habit of following tutorials. Break free and use photographs; or better yet, go out and paint what you are seeing right before your eyes and personally experiencing.
Get to know your subject. Although it's not necessary to know how to draw, it is my own personal experience that learning to draw does indeed make a difference. If you feel comfortable with a subject, it will show in the ending results of how you painted it.
Take your camera everywhere you go. There's a painting out there just waiting for you to create it.
Whether it be drawing or painting, think "essence" when trying to capture your subject on to paper and keep it Simple. Less actually means more.
Leave something to the viewer's imagination. Let him/her fill in the missing bits. Just give enough that tells a story or sets the mood you wish for another to see or experience. This is achieved by being "suggestive" with detail or even how you put your paint onto paper as in broken lines or lost and found edges.
If struggling for simplicity when painting from a photograph.......that is, your mind wants to include every little detail you might see but you don't want to include everything, shrink the photo down in size and paint from that. If small enough, you don't see all that detail which will help free the brain from wanting to include it. (Thank you, Peter Saw, for sharing that advice with me.)
If struggling for simplicity while "on location," sorry but I am not real experienced in this area. I can only suggest to take a photo and follow the tip right above this one.
Concentrate on shapes, lights and darks rather than what the subject actually is.
Find yourself a painting pal.......in your neighborhood or over the internet. Having someone to share this journey with can make all the difference in the world........not to mention added fun. Find a forum to belong to and share your achievements with others; but don't forget the critiqued by others tip above.
Try to find a designated place for painting and storage of your art supplies. It can be a real pain having to set everything up and cleaning up each time you want to paint. You can feel freer if when the moment grabs you, you can sit and paint..........even a quick sketch or doodle. Maybe in between chores or running kids about. Even if just a corner in the living room, bedroom, or dining room........make it YOUR space and have everything ready to go for when that opportune time presents itself.
Save your practice pieces and doodles. Do not be too quick to toss in the trash. One of the greatest pleasures I have personally found is keeping a journal of all my work. It tells a story about me and this special journey I have chosen to follow and it allows me to have a visual of my progress......both lessons learned and my most memorable achievements. Even if you place everything in a box, you'll at least have your work to sit and look through.
I personally keep all my work in either 3-Ring binders with acid free clear document protectors and/or Itowa Art Portfolios if not actually done in journal/sketch books. These portfolios have a protective cover and back that can be wiped clean should something be spilled on them and contain bound acid free document sleeves to slide your work in. They come in various sizes to include large paintings and can be purchased through your major art supply companies. I get mine through Jerry's Artarama as they are the only source (as of the writing of this) that offers a size 4 x 6" portfolio for my smaller paintings.
If you have a computer, find some way...be it scanner or camera...store digital copies of everything you do. A back-up you may wish you had should there be the misfortune of something happening to your original work. In addition, this also gives you a permanent recording of those paintings you might sell or give away as gifts.
Make a back-up of your digital back-up. Hard drives are mechanical and destined to fail you at some unexpected time. Make sure you save all your digital recordings to CD, DVD or some other reliable source. I've learned the hard way that you cannot rely on external hard drives. Just another mechanical device to let you down.
Now ... get those brushes wet and splash some color onto paper. That painting isn't going to paint itself, you know. And remember......................... ENJOY - HAVE FUN.