I created this Google Spreadsheet to help myself with position sizing, and I thought I would share it with you guys. I always have this printed out and laying on my desk while I am trading. I did take this a step further and created a custom keyboard with hotkeys, but I will share that info at the end.
With this spreadsheet you are able to calculate your position size on the fly, just by knowing the distance to your stop loss. By default, the risk is set to 100. This means every single trade that you take, you should lose no more than $100. An example would be, if my stop loss is 0.30 away, my position size for that trade would be 334 shares.
You are able to change the default risk to what ever you are willing to risk, and your share sizes will automatically be calculated.
Here is the link: https://docs.google.com/spreadsheets/d/1iD0qiPLulbYSFri9r38SG1Ke7eNiZdFHNg8MldGwSng/edit?usp=sharing
To use this Spreadsheet:
make sure you are logged in to your Google account, so you are able to copy the spreadsheet to your Google Drive
go to File -> Make a copy... -> Then save it to your Google Drive
Once you have copied the spreadsheet, you can now edit the default risk of 100, and your share sizes will be calculated accordingly
A step further... The Keyboard
Having this printed on your desk does help you easily calculate your position size, but it does have one drawback. You have to enter your position size in manually, which does eat up precious time. I wanted the idea of the chart used as hotkeys, so my solution was a custom keyboard. I have attached the proof I got back from http://www.wasdkeyboards.com, as well as a photo of the physical keyboard.
How it works
As you can see from the images, the distance to stop loss is printed on the alpha keys.
If I have my hotkeys set up to risk 100 per trade, Short+Modifier+E would short the stock with 667 shares:
Risk: 100
Distance to stop loss: 0.15
100 / .15 = 666.6 (667 rounded up)
Conclusion
Having the spreadsheet printed in front of me while I trade really helped with my position size. The keyboard really helped me execute my trades faster.