I'm with the PPs who say you get to say when you want visitors, MIL or not. Aim for twice a week short visits if local unless it suits you otherwise. This is precious bonding and sleeping days when you can, and you don't need to be worrying about a visitor when it's a day you and baby want to just "be".
It's good to get out and join groups and baby might be tired afterwards so you'll be beginning to get a real routine in.
You can always say you'll text mid morning If you are up to a visit later or ask her to come when DH is home in early evening but you say which day.
When my parents visited (they live 3 hours away) they asked, booked it around me and stayed but spent most their time cooking, helping with jobs housework & shopping, so I could rest and focus on baby. They brought me tea and offered to take baby for 20 mins so I could drink tea hot. That was a help.
They were really glad when I suggested they cuddled baby at regular points during day, but they were just glad to see him and watch him play on his mat or in his bouncy chair too. My dad loved entertaining him with rattles and toys. And "chatting" with him. They have a brilliant bond with all my DCs.
They never once asked to walk him to shops or take him out - they'd offer I could ask them but they didn't want to interfere and would do so if I asked them. They asked if I wanted him back if he was unsettled in their arms or could they try, and watched him downstairs sometimes saying I could go to sleep upstairs if I wanted. I realise now how fab and respectful they were compared to other family. They've taken my DC individually on short break holidays too when older.
My MIL was hard work and descended on me for days at a time but didn't help and expected to be waited on. I had to tiptoe around at night when he woke up the house, as she moaned how little sleep she'd had ( 🙄 extra pressure). I liked seeing her bond but didn't like the long stays and old fashioned advice. Gradually her visits became less - twice a year, so they facetimed her.
I drove baby to stay at here before into my DParents and found a 2 hour visit enough as her house was unsafe for exploring toddlers.
My DSis, no children, was fabulous but overwhelming and gave me no space when she stayed (literally sitting next to me and stroking baby feet or hands when I was bf!) . She also expected me to do all the cooking etc. But we were close and I could say 'step back Sis you're crowding me'. She also did everything like nappies so wasn't just about the cuddles, and read every book going and asked my opinion if she could and was she doing it right. She adored them and they her. I really loved their relationship and have no regrets I survived her 6-8 lots of one week long visit year! Once my DC3 was 7 months I was handing her over as soon as Dsis walked through the door with her suitcases 😂