What is the best way to link to an affiliate offer within a blog post?

I have a question about how I should be linking to an affiliate offer from my blog.

Right now every day I post a new, 200 word news summary of what's happening in my niche. I include my main keyword phrase at least once in the post. I bold the keyword phrase, and then link it to my affiliate offer. The link's title attribute is also set to my keyword phrase.

I'm concerned because I seem to be building a lot of link strength for my main keyword phrase that is pointing away from my site, which can't be helping me organically rank for it.

I'm further concerned that my link essentially feels like a bait and switch, as I'm not explicitly calling out that the link leads to my affiliate offer. I'm not "selling" the offer at all, just linking to it within every post wherever I've worked in my keyword phrase.

Shouldn't I be linking my main niche keyword phrase back to my blogs home page in order to help its organic ranking?

If so, how should I be linking out to my affiliate offer? Should I be adding a little blurb to the end of every post selling the offer, and then linking to it?

Also, is it a good idea to be linking to my affiliate offer on every single blog post? On most posts it's the only link.

Or is it better not to link to my affiliate offer at all within the blog posts, but rather point visitors to an internal pre-sales page that then links out to the offer?

I'm really new to affiliate marketing and I'm doing my head in trying to figure out the right formula. I really appreciate any advice from anyone with direct experience and success!