It is a good idea to first write in a programme (off line) that has a spell checker. Then when you have checked it with the spell checker cut and paste your words /text into your hubpages capsules or your blog.
There is a spell checker feature on hubpages text capsules, use it to check again. I try to remember to use that when ever I post an article as spelling mistakes on hubs are not a good idea.
Grammar is also important but I do not know how to offer advice on that apart from reading as much as you can written by as many different types of writers as possible. I mean read books such as novels, read newspapers that are available on line and different peoples' hubpages to give you a range of how English is used differently in different types of writing.
Post script. I have just taken a look at one of your hubs and think you have a style of writing that is interesting. I think your spelling and grammar will improve with practice and reading other peoples' words and that you have originality which can not be taught.