I keep reading that Google penalises guest posting. Is it still a safe way to build links?
Guest posting is safe when it is done for readers, not just for links. Google's concern is with large-scale, low-quality guest posts made only to pass link value.
Signs of a good guest post:
Avoid link farms, sites with spammy topics in their recent posts, and packages promising hundreds of links overnight. A handful of strong placements beats dozens of weak ones.
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