I am writing this particular article at the direction of Thor, a good friend of mine and rather reliable source of help, for this is about his wife, Sif. She of the golden hair is his relatively silent support, but also a goddess of the wheat fields, fertility, marriage, and the fruits of that union. The name "Sif" is the singular form of the Old Norse word "Sifjar", which implies a marital union, and it speaks to her nature as a Goddess.
Not a whole lot is known about her from a mythological perspective, as the Christian man who recorded many of these stories (none other than Snorri) either didn't have much to work with or didn't care to record what he saw as a "minor deity". As such, we have to rely upon inspiration & UPG in order to carry forward and appropriately understand her influence in our lives.
Sif is a deity that I have a relationship with through Thor, rather than the other way around. I met him many years ago, and while he is not a constant companion, he picks up when I call. In those interactions, Sif has always been a quiet, relatively reserved force, but she is clearly powerful and present despite her tranquility.
I would recommend appealing to her for assistance in separating the wheat from the chaff in your life, as well as in bringing grain to harvest in both a literal and metaphorical sense. These things are her domain, and as such she can well assist you in bringing long-term projects to bear in a flourishing, beneficial way.
Likewise, if you seek to marry another, call to her for approval and see what she has to say on the matter. It has been my experience that you will get your signs and portents through other people in your life, rather than through direct manifestations. I can't tell you how many times a woman of blonde hair has, after working with Thor & Sif, delivered a message that felt to be from her lips...
To invoke her, use this prayer, and then leave for her a cup of mead, honey water, or a cut of grain out for her.
"Sif, treasure of Thor,
She by whom golden locks are bore -
I call out to you and ask for grace
To visit itself upon this place.
For I seek boons that are yours to give,
Happiness, joy, and a wonderful life to live.
Bless me and mine with gentle mien,
And loving wits aplenty, kind and keen.
Blessings to you and me, oh gentle goddess.
For we seek to learn to love those with promise.
[Place here what you seek, preferably in rhyme]"
If you're doing this correctly, you'll likely feel a warmness in your chest and a sense of beaming joy that overtakes you. For me, even in the bleakest of days, she feels like a gentle ray of sunshine that leaves my eyes brimming with happy tears. ;)
Blessings to you, and Happy Holidays.