1.Using lot's of paint . I meant it. Lots . This not only will make your painting look more mature, but it will make YOU happier.Trust me ! So give me a favor and buy large tubes of paint.
2. Making every brush stroke count - literally. Imagine you are laying bricks - Brick is your stroke.
Lay a brick after brick , stroke after stroke - leave every stroke alone - leave an integrity of every stroke visible .
3. Making assertive, deliberate and bold strokes with brush full of paint
All three tricks will take time and discipline to develop - but it worth it!