Pull-UPS and push-UPS. So you easily carry this item, learn how to catch up on the bar 10 times, not tucking in his legs and keeping them straight, and exercise from the floor at least 20 times.
Checkbox. The next step is to fix the check box, as shown in the picture. To make it easier to make this part of the element after pull-UPS you can put the forearm parallel to the crossbar, and then out into the box.
To do push-UPS on a horizontal bar. After you leave the check box to fix the second arm on the horizontal bar, as shown in the picture. To make it easier to do it, you can have a little wobble. With this position you need to do push-UPS on a horizontal bar and out on the straight arm.
Be careful when picking a box, since if it is off hand, you can hurt your thumb.
Once you may fail, but the important thing is perseverance and regularity. If you develop these two factors, achieve great results.