Vesp put it very well. Basically there's no one magic way to stay anonymous online, and even when you take all the precautions, there is still no guarantee.
Writing differently (professionally & from an anonymous point of view) won't save you, but I would think it would definitely be more helpful then SWIM or one of SWIM's derivatives. Example:
In order to remove the H2O(water) from C3H6O(acetone) and make the solvent anhydrous, MgSO4 is used as a desiccant. MgSO4 heptahydrate was spread in a fine layer over a baking tray evenly and then set in the oven for 4 hours at 477K. When removed from the oven, the anhydrous MgSO4 was now a brittle white chalky solid piece.
VS
You should spread out some epsom salts on a cookie sheet and cook them in the oven on high for a few hours, thats the way SWIM does it.
Another point made was EXIF data, which are extra details about an imagine file that can reveal personal information. I don't know a whole lot about this, but in order to remove this(or most of) the information, right click on the image(s) an select properties. Go to the details tab and there will be a button at the bottom that says, "Remove Properties and Personal Information." Click it, and when the new box pop's up select," remove the following properties from this file:", click the select all button, and hit OK.
I don't know if this will erase all EXIF data, but it seems to clear out most of it.
Using Tor alongside a VPS is much much better then browsing in plain old Firefox and provides a much greater level of security/privacy on the internet, but just like Blake Benthall, if you become high enough of a target, law enforcement will use more an more resources until they get you. Using public wifi is preferred, but IMO, if they get down to the WiFi you were using, I don't know if using a public one will help a lot, maybe buy you a little more time.
If your not at least using a fake email, then you need to start learning the basics on the internet before posting all over a forum like this, everyone I know has a few email accounts. One main account and usually 2+ junk email/fake ones. Making email accounts is the easiest part, knowing if they're compromised can be difficult, you just need to keep a very close eye out for something that doesn't seem right. This is similar to when someone selling illegal drugs decided to get a new phone, new car, new place, etc. Chances are that if someone manages to get into your account or is watching you, then they'll be careful not to leave any trace. I recommend just getting a new one every so often, like changing a password.
All in all, your best bet is what Vesp said, don't make yourself a target worth their time. The more knowledgeable and experienced you become, the tougher this will probably get. Law enforcement will most likely go after who is popular, knows everything, and does large scale operations rather then track down a million newbees