I am basing my answer on this

I envision as a book in the end.

So my first recommendation is beyond the technical elements you are asking for.

1. Frame a bit wider than the frame you like.

A printed book normally has a different proportion than a 3:2 sensor.

A designer could choose to maintain the proportion of the photo if showing the full image is important.

Or in some cases, the photo can be cropped to give the final product a specific style.

But probably the final design wants to use the photos on a double-page.

Sometimes the background can be extended by copying it if there is not enough, in the case of flat surfaces.

But in some cases, you can not, for example when the background is organic, like some clouds.

Framing a bit wider will give more flexibility when designing the final product.

2. Try not to burn whites

In commercial print the transition from pure white to some sort of color is more pronounced than on screen, so keep that in mind.

3. Configure the camera's profile to Adobe 1998

Although you should shoot in raw, configure the color profile to adobe 1998 if your camera has it. This will embed the profile to the JPG files.

4. Calibrate your monitor (have a good monitor btw)

Buy a device to calibrate your monitor, either a DataColor Spider or an Xrite one are good options.

5. A more in-depth calibration also involves the room you are working in. The maximum brightness of the screen (white) should match an illuminant on the same room to view prints. But this is a bit out of the scope.

6. Use a CMYK profile to preview the result

When you export an image from lightroom this will be RGB and use Adobe1998 color profile. But previsualize it on Photoshop simulating a CMYK one. People recommend Fogra 39, but it has a TOC too high, I recommend an older one Like Swop v2. The colors that can be printed are duller than the monitor.

But DO NOT CONVERT them to CMYK, you should send them in RGB with the AdobeRGB profile. The conversion is one of the final steps of the design process.

Steps I should take when sending the images off to a printer

7. You do not send a photo for a book to a printer, you send it to the designer of the book.

He must have a color-calibrated workflow and work with him so you can see on the monitor the look of the images.

When the files go to the printer he should return to you an inkjet proof with a small difference from the final product. There is always a difference to some degree, but professional people will provide reasonable printed proof.