In my view, when u take action to adjust the delta, the net delta jumps in steps.
Eg - buy futures - delta changes by +1
buy ATM PUT - delta changes by -0.5 (ITM put will have higher delta whereas OTM put will have lower delta)
sell ATM CALL - delta changes by +0.5 (ITM Call will have higher delta whereas OTM Call will have lower delta)
(note - I am taking delta for "each 1 Rs change in the underlying" hence it is smaller number. You can very well use it for "each 100 Rs change in underlying" and the net result gets multiplied by that factor)
For eg - if one has started with +4 delta due created by 4 long futures and -4 delta created by buying 8 put. On 50 Rs. drop in nifty, the net delta will be = +4 for futures (it never changes ideally) but for PUT, it will change from -0.5 to -0.65 (for eg.).. so the net delta now is = +4 - (0.65*8) = -1.2.
So to adjust this whatever step u take, the net delta will not be 0 but some other number slightly away from 0. say in above example, if you sell 1 future, then net delta is still -0.2,
So, IMO, this delta neutral strategy can be implemented effectively if you are trading in large quantity, say 1000 NF contract, then in above example your portfolio delta will be
-120.. which u can bring down by selling 120 futures contract. But for small portfolio, one can't sell 1.2 future contract.
Another points that makes this strategy difficult for small account is the brokerage, the time required to monitor it regularly, liquidity and slippage with each order.
Workaround could be to 1) Instead of looking at ZERO delta strategy, look for say +0.2 to -0.2 delta as acceptable target. And then monitor the position delta on periodic basis say once a day / once in a few days etc and take corrective action to bring the delta into your comfort zone.
Happy Trading