That is some very long hair!
As far as section sizes go, if you make 1×1 inch sections all over your head, you will have thin but manageable locks on your straight hair texture. That is what I did with my last set of locks – I wound up with around 50 and they were thicker than my past sets and they were my favorite by far!
If you follow the video on our sectioning page ( http://dreadlockinfo.com/sectioning ), you should end up with locks that are thicker than a pencil, but maybe a bit thinner than a finger.
On to some additional info that I feel is pertinent:
Now, I need to caution you on starting locks on your long, straight hair. Long, straight hair is the most prone of all hair textures to loop and shrink drastically!
For example, miss margot escargot started with waist length brushable hair and in 6 months, her locked hair has shrunk up to her shoulders!
You can see on her youtube: http://www.youtube.com/channel/UCFDC-ra-Y0pr2413J892_Kg
Here’s her tumblr: http://margot-escargot.tumblr.com/
That isn’t necessarily a bad thing, but it is something to consider!
So, if you want to avoid the massive shrinkage you might experience with locking long, straight hair, you should start with the tightest starting method possible so that they are less likely to warp and change. Backcombing with tight crochet hooking, which you can find more info about and more detailed tutorials on our “starting methods” page. This lovely lady did a great tight start on her locks similar to what you should aim for:
Also, once monthly crochet hooking of your locks will minimize looping, keep them tidy, and minimize shrinking (but your locks will be thinner overall).
All that said, whether you choose to let your hair shrink, loop, and be wild and free, or you choose to keep it maintained and more tidy and organized looking is up to you! It’s all about personal aesthetics. The minimum maintenance you must do is separating your locks daily and washing them regularly- the rest is all personal preference.
As long as your hair is clean and you are happy, your locks will be beautiful.