Anchor text keywprd strategy

Hi there, I wanna do SEO for my friend's website (which is currently in development), say, his websote is about garden furniture manufacturer and his main products are garden pots and water fountains.

as for keyword research, I already did on some terms and the main keyword for the business is "Garden Pots" and "water fountains" (of course the competition is very high for those two) and the less competitive but long tailed is like "Indoor Terrazzo Garden Statue",

so, my option is:

1. I try to optimize main keyword by doing link exchange, should I use (only) one of either "Garden Pots Manufacturer" or "water fountains Manufacturer" or try to use both like "Garden Pots and Water fountains" for the anchor text which links to Homepage? what is the suggestion? (this way I can optimize water fountains or garden pots).
and I only optimize less competitive keyword too (anchor text "Indoor Terrazzo Garden Statue" which is links to relevant page, not HOMEPAGE) by commenting in dofollow website or blogs,

2. or, should I use the same terms for all anchor text (one of "Garden Pots Manufacturer" or "water fountains Manufacturer" or "Garden Pots and Water fountains" or it can be "Indoor Terrazzo Garden Statue") by exchange links, link submitter, commenting etc?

Thats my question, many thanks for the replies