Some people like to use outside photo hosting services (like photobucket) and then simply insert the code.
Or, to add photos directly into your post without hosting elsewhere, you simply add as an attachment. When you are typing your post, below the box you will see "add an attachment." Click on the "browse" button and find the photos on your computer. Then click "add attachment." If you are on a slow connection and the file is large it can take a minute or two to upload. You can upload 3 into one post. If you have more photos, then simply reply to your own post and add more photos.
To cut down on upload time and have photos load up more quickly for visitors, you should try to reduce the file size of your photo. This is something you would need to do on your computer before uploading.
When it comes to scent, there are basically two types; those that attract and those that mask. I've tried both on many occasions. There are lots and lots of "doe in heat" scents, designed to attract a big buck into range. I've also used a "cow in heat" scent while elk hunting.
Another scent would almost be better named as a "coverup smell". The main goal is to cover up human odor or mask it. Though I don't believe you can ever totally eliminate all human...