This was my approach using some facts I'd known- At cathode and anode of a cell reactions take place making positive terminal positively charged and negative terminal negatively charged I.e. there are more electrons at the negative terminal and dearth at positive .When connected by a wire electrons of the wire move towards the positive terminal and when some enter the terminal the others depart from surplus hoarded electrons at the negative terminal causing a continuous flow of electrons .
Please help if i went wrong somewhere.