I am working on a homebrew for a domain and am having trouble getting a particular ability to work correctly..... I am hoping that someone here may have some expertise, insight, and/or knowledge 'Beyond' my own as to how to get it to work. Below I will place the text of what the ability does.

You may prepare one spell of 1st level from the wizard spell list. When you reach 3rd level in this class, you may prepare one spell of 2nd level from the wizard spell list. For each odd level you have in this class, you may prepare one spell from the wizard spell list of the highest level spell you can prepare from this class at that level. These spells count as cleric spells for you when prepared in this way.

I also chose some of the particular wording to keep the ability from being abused through multiclassing.

If anyone knows how I could get this to work correctly, the help would be greatly appreciated.

Thanks

People in the Homebrew forum might have a better idea :)

There's two ways depending on what you want. One way is closer to what ya seem to want but a nightmare and the other is easier but you may want to balance it. 

Trying to type it out and make screen shots would take too long. I tired. So I made a video. Here ya go.

In addition to the video Cyb3rM1nd posted, you can likely find helpful information in the Subclasses & Races FAQ #15: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).

Thanks for the response guys... much appreciated.