I was in charge or streamlining our ad-setup process and was able to turn a pretty broken process when I arrived (not finishing until NOON! sometimes) to finishing before the lights went on 95% of the time. When I started, they would scan the entire ad in at 4AM to fudge the numbers then lazily put the signs up as the day went on. The DTL had caught onto this trend and had put the hammer down on my STL - me being a new ETL-LOG at the time - it became my new challenge.
The first step in ensuring a really good ad-setup is having a really good ad-prep, this will save you so much time when actually putting up the signs. Make sure you ad-prep team is sorting everything properly - they should run the reports and actually walk the floor to make sure come Sunday everything runs smoothly and is in order. Clearly marking some ads with END-CAP (vs just putting (0)) saved a lot of time because the team understood these signs NEEDED to go on the end-cap.
The biggest report (the name is escaping me, I've been gone from Target for too long now...) actually told you which signs you could safely throw out, which eliminates some double-work, but you still have to be careful because sometimes the report went crazy and told us to throw away 15 pages of signs, which obviously was wrong...be smart about it. Also, the prep team should put all the extra things the team might need when setting up (sign holders, clips, etc) with their signs. The last thing you want during setup is everyone walking across the entire store to the signing room every 10 minutes just to get one sign holder...
Also, the green-dot prep for softlines (not sure if its still a best practice considering softlines BP seemed to change several times a year for signing...) saved us so much time putting up softlines ads. The softlines TL or brand attendant, should walk the entire ad prior to Sunday to help the team place signs up. When we did this, Softlines was usually done before the rest of the store.
Being in a 4AM flow store, I was used to getting there early. So on Sundays with no truck, I'd get in at 3:30 and start prepping for the setup. I'd move all the waco-boxes with signs into carts with all the holders, headers, etc and move them out to the section they belong. I'd also print out the summary of end-caps for each section so they could do them with the rest of the setup. At about 4-4:15 I would start putting up the signs in the easy areas. I'd have plug, office, one spot/checklanes, home and part of toys done before the team arrived at 5AM (usually 5 people with one TL). Once they got there I had a small huddle and we sent the entire team to the biggest section (often grocery or HBA) to blitz through it. As they went through the section I walked a step behind them auditing aisles and end-caps and make sign batches where needed. Once the team finished the biggest area, I split them off to tackle the left over areas. Know each individual's strength here - don't put someone in electronics who has never seen the browser before or softlines, etc.
It took a while to get it going but we eventually got into a system where we were always done around 7:30 and the TL and I would finish auditing the ad and printing missed signs. The biggest thing I learned was its not about the number of people or taking "strong" team members from through the store - it's about drilling in the process and having them understand why it was so important and rewarding them for meeting the goals. If the team finished on time and the audit was done - everyone got breakfast, every week. Free food may be the secrets to all your struggles :O
I know a big concern is payroll - this was in a ULV store that sometimes got as little as 1000-1100 hours a week for the entire store. I made a business case for the STL on why I felt signing should have their hours adjusted and he agreed. If the store is not willing to make any changes to improve the process, it will never change.
Hope some of that helps, again BP may have changed as I stopped working for Target about little over a year ago, but the idea should be the same!