since i've been away from tapas off n on (A LOT) it's tough to keep up especially with a reading list thats close to 1k depending on the day its basically just time and patience 
usually my go to has been binging things at once but for longer comics i'll usually pause when i feel like i can't keep reading or need a breather and tab it off either in my actual browser bookmarks or make a note in my personal discord server. it's the same method i use for independently hosted webcomics so it's at least a system i know and feel comfortable with
i think the only time it gets tricky is when i end up forgetting the plot for longer form/story based comics which kinda makes me feel bad so i try to wait till their done or binge em exclusively till i'm all caught up
if anything though having such a long backlog has pretty much stopped me from subbing to anything new unless it's also already done or genuinely looks interesting enough for me to wanna keep up with. it hasnt stopped me from checking out fics or comics on other platforms though but i tend to better keep up with those than stuff on tapas 