IMO you are doing it the right way. Slowly buy. Right now oil is down 40% and the market down basically 20%. Buying now is certainly not buying at the top. Those calling for oil to go to $35 could end up being correct, never know but first it must break below $45 then $42 and then $38.
Anyway everything is extremely oversold and everything is so negative. Buying now will bring a good return. It will take time though and your current strategy of slowly buying is the correct way in this environment. I am doing the same. We are not buying the October prices. We are buying now and dollar cost averaging and that strategy worked in early 2016 and in 2009. By May we will probably be in the green and by a lot. Hang in there.