I second what Will says about approaching these entities with caution and the utmost respect - especially if you are uninitiated, working without a teacher, and/or from outside Their native cultures. There are some spirits/Diety forms that are generally "safer" for the newbie to work with - such as saints - but the Orisha and Loa don't fall into this category.
I agree with You both , Vodou requires either initiation or becoming "compadre" ( Santerian term ) with them .
Yet In Creole , that specifies in 7 African Powers work , mentioned above ( also called New Orleans Voodoo , or just Voodoo a NO Vodou branch ) it is considered that anyone can petition 7 African Powers .
However Ellegua ( Papa Legba ) as a fairly benevolent entity and interceding Spirit has role of helping safe and successful communication with rest of Loas .
Also Pater Noster , Credo and Hail Maries , along with prayer to the Seven African powers is done prior the petition as another precaution and safety measure .
Therefore when done properly , working with this spirits is harmless , that of course requires good knowledge on each of them and respect. So Yes not suggested to any newbie .
As for Loas beside Ones I mentioned here , You do need initiation or at very least great amount of knowledge and respect . I would approach with utmost care to any of Guede Loa family ( Maman Briggit excluded as she is quite mild and nice )
or for Example Damballah .
However there are still some Loa beside the Seven African Powers that are safe to petition ( Marie Leveau , Li Grand Zombi , Petro Family many of them ), but as You kindly suggested that would still be a better idea with initiation .
Thank You both all for Your comments I began to think no one will read this lol :)
Well seems like a typical error newcomers to Vooodoo make. She must have had invoked Yemaya alongside Oya or any of the Cimetre family, particulary If she had money issues, and that is not done.
Of course the lack of respect does not help at all . But I have a habbit of saying one who drinks a liter of liquid labeled Caution , carelessly is one who is to blame.
As for veves someone requested . I am sorry but we can not upload pics here.
Summary of the Five Nation's, the content i am adding was formed with the guideline's of Denise Alavardo's and her book The Voodoo Hoodoo Spellbook and a few other's, all my sources are below, they helped me learn about the Five Nations and the specific Lwa throughout the year's, and i would recommend reading all of them to extend your knowledge of this practice.
The Lwa Nations
The Nation's are categorized into five major families of the Lwa spirits, hopefully after reading my descriptions and sources you will have a better understanding of what each Nation consists of. Keep in mind some families in the Loa are mixed, so one could be two of the Nations, please enjoy and feel free to add in informative information about the Lwa Nations.
The Five Nations
Rada - The benevolent Lwa's of Wind, they are generally helpful to us, Rada are guardians of morals and principles and are associated with the element of air, their origin's can be traced back to Dahomean Vodou. Legba, Loko, Ayizan, Damballa Wedo and Ayida Wedo, Erzulie Freda (Both Rada and Petro), La Sirne, and Agw are some of the Rada.
Petro - The Haitian fire spirits are much more temperamental and aggressive than the Rada. Petro or the "demon spirit's" were made under the harsh condition's of slavery. These are the Lwa to call when you seek revenge and want to conjure up something extra special. Erzulie Dantor is the "mother" of the Petro nation and is one of the most important Petro lwa. Petro Lwa's include Erzulie Dantor, Marinette, Ogun, and Kalfu (Carrefour).
Congo - The African water spirits hail from the Congo region of Africa and are also found in parts of Northern Haiti. Most of these Loa i have learned to be quite disturbing but extremely protective of their people. Like Marinette is said to be feared but free's her people from bondage, and then you have Congo Savanne who grinds people up like corn for snacks.
Nada - These contain most of the Ogun Lwa, those who walk the path of Nada were unmovable and never wavering, they stood up for what they believed in and walk in death with the Ogun Lwa some of them being Ossange, Brize, Ogou Badagris, Ogou Demannier and so many more.
Guede - Spirits of the dead and fertility make up the Guede, they are ruled by the Barons (La Croix, Samedi, Cimitire, Krimine) & Manman Brigit who is the wife of Baron Samedi. These spirits are the life of the party but they tend to get carried away, after all they do enjoy their humor and rum. Other Barons like Baron Kriminel or the Baron of Criminals was the first murderer, and so he is in charge of murderer's and when called upon he will send his horses to exact revenge on the person who did wrong.