Jyeshta Laxmi is the exact opposite of everything that Laxmi stands for. Jyeshta is said to be the elder sister of Laxmi. This means she manifested before Laxmi; before wealth there was no wealth; before prosperity there was misery; before enchanting beauty there was ugliness; before auspiciousness there was in-auspiciousness and so on if one takes the literal meaning.
However the deeper meaning of Jyeshta is all that which existed before all that is attributed to Laxmi came into existence. One can argue that before everything there existed nothing, but one must not forget that nothingness just cannot exist without there being a something or everything Both Laxmi and Jyeshta Laxmi are thus the two sides of the same coin; the un-manifested and the manifested. Hindu sages understood this and also worshiped Jyeshta Laxmi to make Laxmi manifest into their lives.
A simple way to invoke Jyeshta Laxmi is to say a small prayer to her asking her to make Laxmi manifest into your life and fill your life with abundance and inner and outer beauty.