First off you want to start by selecting seeds from your plant that are fully ripe
Deep red to purple is the colour to look for before picking
Put all your seeds into a glass jar and fill with rain water and place in a sunny spot
Leave 3-5days
Water may turn off off colour and get bubbles _ don't panic this is exactly what you want and part of the process
Drain water with seeds into a sieve
Next take a seed in between thumb and forefinger and gently squeeze
Your seeds wil now easily pop out of the soft outer flesh
Give the seeds a good rinse whilst gently rubbing to remove any last little pieces that didn't come off whilst squeezing
Take your sieve and place in sunny position for a few hours
Congratulations!!
You now have nice clean seeds ready for storage// planting
Fresh seed greatly increases germination rate so don't leave them too long before planting