RE: updated list from Parob8 Apr 2021 18:06
Foolsgold - it very much depends on the share, how I believe it's valued, future prospects etc. Companies that have seen a surge in sentiment are often worth slicing more - I'm invested in GDR and regret not slicing a couple of times, my average is 110p. I believe it will still come good so not hugely concerned but it's definitely underperformed expectations.
In general terms, I would say 20-40% on average in terms of slicing. I sliced 40% of AVCT in 3 tranches recently. That was more than I wanted to but I also wanted to use up my Capital Gains Allowance for the last financial year before it closed.
Slicing is the best form of risk management, and most would say you should slice (as a minimum) the amount you originally invested, so you have 'free carry'. I sold all of my Ceres shares last year. I doubled my money when I sold out at £6.50. It's not trading at £12. I should definitely have left some free carry there!!!
Anyway, good luck with whatever you choose. Locking in profit is never a bad thing, even if you can kick yourself sometimes at what might have been. Best advice I can give is not to get too emotionally attached to a company/share - this clouds your judgement