Add images or drawings to sheet

I need the branding and three product sketches embedded in the January metrics sheet so the investor deck reads as one file. Put the logo in the top-left of sheet Cover, lock its cell so rows don't move it, and place the three sketches across cells B4:D10 on sheet ProductSketches, resizing so each fits in its cell without obscuring the January totals. Check the images display on mobile view and do not push any formulas off-screen before I send to Priya on Friday.

Before I share the workbook with the operations lead, make the added images easy to spot and non-disruptive. Put the logo on a dedicated Cover sheet with a tiny caption saying source and date. For the sketches, use Insert Drawing so they stay crisp, anchor them to cells B4, C4 and D4, and reduce each to 250px width. Flag any formulas or frozen panes that the images would cover and mark them with a yellow comment for reviewer attention.

I just pasted a 4MB PNG into the January metrics sheet and it displaced the frozen header so totals scrolled away; Finance will complain and I cannot tell them the file is still editable. I am afraid the sheet will become slow for the team and the image will misalign when they open on a phone. What likely went wrong and what are the fastest, safest fixes so I can restore the header and keep a usable image for Friday's investor call?

Across the quarterly decks I keep pasting high-resolution art; each time someone opens the sheet the frozen header jumps, formulas lag, and we waste hours reverting. I want a repeatable habit that prevents this and keeps the workbook lightweight for analysts and the investor team. What rule should I adopt when receiving art, who do I ask to optimize it, and what steps save time every time I add visuals?