Relevant links from nontoxic web properties will help.
They need to be relevant to your niche, avoid sites with inflated SEO metrics but minimal organic traffic.
Avoid link farms and generic multiniche websites that have high OBL.
.GR & .COM both will help don't just concentrate on one diversify your link profile and anchors.
Percentage of branded anchors should be higher than the generic and keyword anchors.
Also, pointing majority of links to the homepage helps.
Build topical content maps (site & content structure) across different topics to improve topical authority on your websites and interlink them.