You will need  :

Use 2"x1" planed all round softwood, cut to required proportions.

1/4" x 1/4" beading strips can be made for you by any good wood yard for next to nothing.

Size 8 x 3/4" wood screws

1" veneer pins 

Canvas selection should be as follows :

8oz - small paintings no larger than  2' x 3'

10oz - mid-sized paintings up to 5' x 4'

12oz - for small to large paintings up to 7' x 5'

14oz - for mid to large size paintings from 4' x 5' upwards

Primer and/or rabbit glue size