Using the basic chords, a left-handed player can place his fingers on the same set of strings only that it has to be put the other way around but with the same basic strings. Regardless of how accustomed people are when it comes to playing a guitar right handed, some left handed guitarists have introduced newer methods.
To start with, you should equip yourself with a guitar guide or manual. Playing with an upside down guitar doesn’t necessarily mean changing the mode of how fingering should be. The placement of your fingers would still be the same although the only difference would rely on the finger you use on the fret of the guitar. Normally, if you would play a right handed guitar right handed, the C would represent that your fourth finger must be positioned at the third fret dipping on the fifth string. Then your third finger must lie on the second fret pressing on the fourth string. Last, your index finger must be on the first fret down on the second string.
With an inverted guitar for lefties, it should be done in an inverted way too. Noting that your last string would be on top and the fret would remain the same. Things are difficult if you have no guitar to practice with. Make it a point that you follow what the diagram shows and not making the mistake of strumming the forbidden strings in each chord.
This type of technique is difficult, indeed. So start with those chords that only require three or three fingers at the moment. Basic chords like CAGED or some minor details. When you get the hang on it, try working on the harder ones. Do not saturate yourself with learning the hard ones first. That would be enough reason for you to give up. Frustrated.
But if you find it really hard to cope with this kind of style, settle with the conventional way of playing. That is, playing a right handed guitar right handed even though you’re left handed.