Start with sloe Gin,
i use 1 litre Gin per 1lb sloe to 1/2 lb sugar... shake each day until all sugar gone, then weekly
after min 4 months, i use coffee filters and re bottle the sloe gin, you can add sugar at this point if still not sweet enough.
take used sloes and add 1/2 lb to 2 litres traditional cider..... filter and drink after a month.... SLIDER
take used sloes put .75l Port in 1l bottle, top up with used sloes from gin, leave for min 6 weeks....sloe port