Mackerel is probably one of the baits that you can use at
any time of year and have a reasonable expectation of catching something. It's readily available in fish shops, supermarkets
and online. It's cheap and cheerfull and you can even just catch your own in summer and freeze it down for winter. One freezing
is probably about enough for mackerel as it loses it's effectiveness with thawing and re-freezing. It can be used in practically
any shape and size for all sizes of fish from small thumbnail size pieces for small fish,thin strips for flounder,whole fillets
for cod,and whole mackerel for conger.
This is just how I would typically mount a small fillet for
cod. For short lobs it will go as it is,for further casting whip up once more with bait elastic.