Buy LGB point motor and momentary switch unit. Power via your transformer. Ensure instructions are included. Read instructions and follow to the letter.
In use apply WD40 to point mechanism at regular intervals and regularly check for debris fouling point mechanism and check rails ( e.g. ballast, twigs, nails, etc). Don't forget to use LGB graphite paste, or similar, on all electrical connections to minimise any electrical conductivity issues in the longterm. Occaisionaly dismantle point motor and give a good clean out, garden bugs !
After 5 years of operation rip out all the electrical gubbins and go back to manual operation. After another 5 years replace manual operation with fancy air powered point actuators. Much less maintainance and groveling around on the ground.
Max.
I guess tha wraps up my learning curve with powered points.