If you are looking to create your own block man or woman in minecraft with customisable options there are three ways you can.
Jump to: 1st Way: Official Game | 2nd Way: Skincraft (Web Browser)
3rd Way: 3D Skin Editor (Android)
1st Way: Official Game

One is the official route, which is the minecraft character creator that will be rolling out soon in the game. You can click here for the latest information on the character editors development and even take part in Beta Testing.
2nd Way: An Adobe Flash Web Browser Tool Known as "Skincraft"

The second way which will be available until browsers like Google Chrome stop Adobe flash working, is a browser tool known as "Skincraft". A powerful avatar creator with pinpoint design potential.
For the Serious Crafter
Create a Minecraft Character with possibly the best skin maker available for free online. Customise your character's blocky appearance with this intuitive tool.
Minecraft is no small craze. The game basically consists of a sandbox environment where you can create and destroy almost everything you can see. To the uninitiated it may seem like an unattractive mess with too many visible pixels and repetitive tasks to complete. However, the program has been used by many as anything from a simple pastime to a tool to create some pretty impressive stuff such as the Univeral Death Clock, a counter that, providing the device running it lasts long enough to allow it to keep running indefinitely, will count down to the end of the universe (which will incidentally end before the clock finishes its mathematics-based countdown). Looking at the fun side of Minecraft however, many enjoy it as a casual game to play, but they can enjoy it more if they’ve created their own customised skin with Skincraft. A simple flash-based application that gives players the power to create their own Minecraft Character Skin Online, Skincraft is a handy tool for the serious Minecrafter.
Play Skincraft
Mein Kraft
If the general audience/player base of Minecraft is anything to go by, then Skincraft would need to be a pretty functional tool if it is going to be respected and not laughed at. Luckily, it is a well-designed application that allows for some pretty in-depth customisation of Minecraft characters. Its interface is similar to any other avatar creator like Sonic Character Designer or Pony Creator, only it is styled after Minecraft’s distinctly pixelated appearance. From the main menu you are given the option of creating a new skin from scratch, loading one that you may have created and saved earlier, importing PNG image file for editing, or viewing the uploads of others, whether for inspiration or for using them in your own game of Minecraft.
Down to the Pixel
The meat of the action is obviously in the editor, which can be found under ‘new game’. From here, you can choose to base your skin around an existing model or a blank skin that comes in a small variety of colours. Unlike many other editors however, you aren’t presented with reels of pre-determined options, but rather a menu that breaks down the various body parts, drilling down on any one of which comes up with a pixel grid that can be drawn on in a freestyle manner. The avatar is constructed from individual layers, much like in Photoshop or Paint.net where you can add a layer and customise it by either drawing it pixel by pixel or selection a few pre-set options as well. This allows you to customise every single pixel or draw inspiration from pre-existing ideas, which makes Skincraft quite a powerful tool for Minecraft fans, as well as lives up to the expectation of said fans for anything Minecraft related to be extremely customisable and intricately designed.
Useful but Specific
Of course, Skincraft is a very specific program for a very niche market, namely fans of Minecraft, but so is pretty much every other game in this narrow genre. Pony Creator deals with equine customisation; Sonic Character Designer deals exclusively with characters from the much-loved video game series; Skincraft simply fills another niche market, but it does so with a program that lets you customise down to the pixel level, making it one of the best avatar creators around.
3rd Way: Skin Editor 3D for Android by Remoro Studios

The Skin Editor for Android comes with 200,000 free skins to further editor or just use as they are. The app supports both 64x32 (old version) and 64x64 (new version) skins. Theres a paint brush and bucket, color grid and gradient selector and eye dropper. The export options for the app are exporting directly to Minecraft Pocket Edition or to your gallery to use with the PC version.