custom rom please help topic

hi people please help me with a guide for my phone? i have read how to do it but i cant seam to find instructions for my device? and my version of android? and dont want to brick it?
i have a sony xperia m single sim model c1905 and its running android 4.3

i have successfully rooted and im looking for the next stages to get a custom rom that has the ability to install apps on my sd card? any recommendations and tutorials would be much appreciated cheers