Drawing. Everyone does it, even if its just sketching, doodling on some math homework, or going full out sketch, ink then color. I've been drawing my whole life, and I've had some friends of mine ask me for help and how I became so good at it. Well, first obvious peice of advice is Practice. Start with something simple, such as a butterfly, and work from that. Now onto some helpful advice. All this advice comes from personal experience and techniques I found that help me, hopefully they can help you as well.
What is a good start?
For starting, decide what you want to draw and work from that. If you want to experiment with fun poses, look for a reference and use a stick figure to plan it out. Once you are happy with the pose, start adding definition with shapes. Remember, the human body is made of different shapes. The torso being a square, arms and legs are cylinders, the head is a circle, and so on. It makes the process much easier.
After the body has shape to it, you can start smoothing out the edges and adding curves. Add muscle shape, rib cage shape and all that fun stuff. If you get confused, look up a reference of the human body. It never hurts to use a reference.
For creatures, you can get very creative. Decide between a real animal or a made up one, and start similar to how you start the human body. Stick figures are very helpful to start any drawing, acting as guide. Just remember, the body is made of shapes, this goes for the creatures as well.
References and Edit Overs
References are a must have for an artist, they come in handy for poses, body types, hands and feet. One thing I know artists hate to draw are hands. If you are one of those, all I can say is be sure you have different hand pose references near by and always practice doodling hands. Like the rest of the body, hands are just shapes when you get down to it. My advice for hands, start out with a skeletal structure, add shapes, then add the curves and suddenly you have a hand.
Now edits, these really irritate me. Edit overs are usually screenshots taken from anime, and painted over to look like someone's custom character. Some do it just to be silly, but others actually try to claim it as their own. This is a no no. The worst part is when someone calls them out on it and they deny it, when it's clearly obvious where the original screen shot is from. Just don't do it, that is all.
When drawing, never limit your skill to one specific style. Branch out, draw mythical creatures, animals, people, scenery, cars, whatever you feel like drawing. Even go between cartoon, realistic and painting. The more you branch out, the more comfortable and confident you get with your own skills.
It never hurts to get drawing books, in case you get stuck on a certain style. Going beyond your limit can also assist in helping you find your own style. Everyone has their style. Some draw in just ink, others stick to digital, some even like to mix pencil and paints. The possibilities are endless! Just explore each area, find out what works for you.
If you start to feel a bit overwhelmed or stressed from drawing, take a nice breather. The more irritated you get, the less inspired you will be and less willing to draw anything. Take a nice break, go for a walk, get a drink, watch a movie, eat something, or whatever you do to de-stress yourself. Stressed drawing takes away the fun of it and makes you never want to draw again.