Please find the attached Yantra for Shani, Rahu and Ketu respectively from left to right.
Shani yantra has to be written in blue color ink in 8 x 8 inch or centimeter and Rahu yantra to be written in black color ink in 4 x 4 inch and Ketu yantra to be written in grey colore in 7 x7 inch on white paper A4 size. individually.
Along with this write mula mantra in hindi and Sham in hindi at all the four corner in shani yantra, and Rum in hindi at all four corners in rahu yantra and Khem in hindi at all four corners in ketu yantra.
Place these yantras in pooja room and use as adviced.