Iv been making my own e juice , I can't take too much PG as I get swollen glands and a lump in my throat ! So I got 100 VG and flavour concentrate , I read somewhere to use 20 % flavour concentrate ? Does that mean , if I make 10 mls of e juice , do I add 2 MLs to 10 mls or do I add 2 mls to 8 mls ? Iv asked and sum say to add 2 Mls to 10 , others say add 2 Mls to 8 ? Which is it please help ? Confused vaper