I'm in a similar boat, kids age 6 and 3. Decided to split 4 or 5 months ago. We haven't told them we're splitting up yet but doing more things separate like alternate bedtimes and have done separate holidays this summer. I'm really hoping we don't have to sell the house to minimise upheaval for them, but waiting for public sector pension amounts to come through - it will depend on that. Like you, I want to have our living situation settled before we break the news.
I'm quite enjoying having time back to myself, I'm doing a jigsaw, very rock and roll! I keep thinking of going to a yoga class or something, but it's hard to get confidence back isn't it. I have started doing couch to 5k but not very often.
I'm finding it difficult that now we're separated we're getting on much better. And I keep remembering when things were better between us (before kids). It helps me to keep a list of all the annoying or unpleasant things he has done to remind myself I'm doing this for a good reason.
If it's any help, I asked my 6 year old what she thinks it must be like for her best friend, whose daddy lives in a different house. She said "exciting", which I was surprised by, but I guess the idea of having a second bedroom is tempting at that age!
Keep us posted how it's going. I feel completely in the dark with all of this.