Thank you for explaining.
What does this mean "keep the dangerous anchor texts - the exact and partial match ones - under 10% of the total anchors of the backlinks that point to that page)"
Let's say you have a car repair site called StarforceCarRepair.com, and you have 3 pages that you wish to rank in google, which are called:
BMW Repair Parts
Ford Repair Parts
Mazda Repair Parts
When you build links, the text that gets chosen as anchor text can be anything you want of several types of anchor texts. For example, for the "Ford Repair Parts" page your backlinks could link to this page using any of these anchor texts:
1) Brand anchor text (ie anchor text that mentions / includes your brand), such as... Starforce Car Repair, Starforce Repair Parts, Starforce Ford Repair, Starforce car repair, etc... Any of these anchor texts are considered branded anchor texts because they include the name of your brand (Starforce)
2) Exact match anchor texts (these are anchor texts that include ONLY the keyword you wish to rank for). For example, for the "Ford Repair Parts" page let's say you target the keywords "ford repair parts" and "ford repair autoshop" and optimize your page (Ford Repair Parts) for these 2 keywords...
In this case, if your backlinks contain the exact same words as the keywords you target (in your case these would be "ford repair parts" and "ford repair autoshop") then they are considered exact match anchor texts because the anchor texts... well... they match your target keywords exactly
The exact match anchor texts are some of the most powerful ones when it comes to ranking, but google knows this too so when they see lots of backlinks with exact match anchor texts they consider the people that built those backlinks to know what they're doing, which is using these powerful anchor texts in order to gain good rankings as google favors keyword relevancy in backlinks... or they used to favor this, I don't know if these anchors are as powerful as they used to be but they still have some power for sure...
These exact match anchors are / have been very powerful in ranking, so if you went overboard with using them you could have gotten in troubles really quick, which is why I've said they are very dangerous...
And the same with the partial match anchor texts. Partial match anchors use some variation / part of the keyword as backlink instead of the entire keyword. So, in our example, a partial match anchor text for the keywords "ford repair parts" and "ford repair autoshop" could be any of these:
- ford repair
- ford parts
- ford autoshop
- repair parts
- repair autoshop
- ford repair parts in Michigan
- Ford parts autoshop
- Repair Parts for Ford
- Autoshop for Ford Repair
- Ford Repairing Parts
- Ford Autoshop near me
- etc.,.
Basically, include any word / any combination of the words from the main keywords in your backlink that are not exact match and you've obtained partial match anchor texts...
I don't know how dangerous partial match anchors are, so I can't speak about them as I simply don't know. But the exact match anchors are very sensitive, so you shouldn't abuse them. If you buy 20 backlinks, for example, and these backlinks have different degrees of strength and you intend to point all 20 links to the same page (let's say to the "Ford Repair Parts" page), you should use exact match anchors ("ford repair parts" and "ford repair autoshop") on maximum 10% of these 20 backlinks, so this means up to 2 times for each keyword each, and preferably only for the best and strongest links, while the remaining links should get either branded anchors, or naked URL anchors, or generic anchors... ok, maybe throw 1 or 2 partial match anchors in there, too for diversity purposes...
So, 10% of 20 links = 2 anchors, and since you're targeting 2 keywords with this page ("ford repair parts" and "ford repair autoshop") you can use up to 10% of the anchors as exact match anchors, which means 0 to 2 of those 20 backlinks can have the exact match anchor "ford repair parts", while another 0 to 2 links can have the other keyword (ford repair autoshop) as exact match anchor...
Sometimes you can get away with more than 10% exact match anchors, but I've always kept them under 10% because I'm very panicky
But there are people who go over 10%, so it's definitely possible to be safe by abusing these anchors (especially true for big sites which google shows more leniency towards than for smaller sites). But like I said, I always preferred extra safety, which is why I kept these anchors at around 5-6%
do i have to diversify anchor texts and not have more than 10% of same or variation of keywords?
yes, having diverse anchors is best...
If you have a branded site use branded anchors for your homepage (you can have anywhere between 30% and 60% as branded anchors without running into issues, the rest of the anchors can be generic or naked URL)...
And for your inner pages (blog posts, for example) you can use a mix of exact match + naked URL + generic anchors (visit us, our blog, at our shop, on our site, click here, check us out today!, this car repair shop has the solution, etc...). I've heard someone say that it's not recommended to use branded anchors for inner (content) pages, but I've not asked why, so I don't know what the reasoning is (or whether this is even true), but if it's true you might not want to risk it. So keep the branded anchors for the homepage only and you should be fine!
What if i want to rank for only 3 to 4 keywords?
get creative (while still not abusing the exact match anchors)! You can use each one of those 3-4 keywords as 1 exact match anchor for 3-4 backlinks, and the rest of the backlinks (assuming they're not that many) you can use generic anchors and naked URLs as I explained above).
Also, if those (or some of those) 3-4 keywords are not that important / hard to rank you might not even use them as anchor texts, sometimes optimizing the content with these keywords is enough for google to rank this page for each one of the keywords, you just have to test and see. First, optimize the content for these keywords (which you should be doing anyway), and then start building links and if you don't see these keywords ranking at least in top 20 you can build a few more links with them as exact match anchors and - if the keywords are really not that hard - this almost always guarantees rankings (assuming that everything else with your site is OK, of course, because if you're using a penalized / blacklisted domain for example you can build as many links as you want and you probably won't rank squat if google hates your domain to begin with

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