Due to budget constraint, i use the following method as i feel its the most cost efficient way, it is to go for full clearing for any particular section you have selected be it the upper lip, lower lip, or chin for each of the session.
The reasoning goes like this, electrolysis works for hair mostly in the anagen stage, so if u clear a particular section eg upper lip in the 1st month. You can concentrate on another section eg lower lip for the next session in the 2nd month and using whatever remaining time leftover for the upper lip regrowth. Then in the 3rd month go for the chin.
You will have up to 16 wks interval of anagen stage for the regrowth period for the first section from the time of the 1st clearing. So in the 4th month go back to the 1st full clearing section and proceed for the 2nd full clearing of that particular section.
You can space session closer together if your budget allows, just aim for full clearing of whatever section done and do the next full clearing within 16 weeks. This way is to can ensure the hairs cleared subsequently are all in the anagen stage, making the whole process more cost effective as you dont waste any time on the talogen and catagen hairs during the subsequent sessions.
Also point to note this that E will slow down the regrowth process, decrease the pain threshold. Plus also the tech skill play a important role, her kill ratio for treated hair, can varies from 30percent to 90 percent .