You don't have to ask another website owner if you can link to their website.

They will be very pleased with the incoming link. But....

If you are going to ‘list’ links, include a small paragraph explaining why they are listed, why they may be important to your reader e.g.

Tessa Copland  |  Editing, writing, content strategy
Content that makes sense. Are your messages clear and easy to find? Catchword gets the right words in the right place on your website. www.catchword.nz

Much better than just a list of links that your reader has to wade through and see if there is anything useful to them. Plus those small paragraphs will contain useful keyword phrases that may be good for optimising your website ad improving the ranking.

NOTE: I haven't asked Tessa's permission, but now my paragraph is published, I'll let her know, and maybe she will link back to me! Its all good where Google are concerned.