Idea: small 6 or 12 number bet on the "dominating/hot" colour (Red or Black). Each dozen contain 6 Black & 6 Red numbers. Consider these 6 groups then: Red Dozen 1, Red Dozen 2, Red Dozen 3, Black Dozen 1, Black Dozen 2, Black Dozen 3. Then bet on the 1 or 2 group of numbers that appear to be "hot" at the time. Look at the last 12 spins & from them judge the current hot group in the hottest colour (or 2 hottest groups in that colour).
Theory: had a session last night where i kept noticing that the "hot" numbers usually grouped in colour/dozen, like Red 1 in 3, 1, 5, 1 or Black 17 in 17, 17,13, 15. But hot numbers seemed to keep changing quickly. So began to manaully track the 6 groups and noticed that a group could easily sleep/go cold for 20+ spins, but would catch up later of cause. So after playing a bit with single "hot" group & it worked well (nice long safe-ish progression). Afterwards played the 2 hottest groups in the hottest colour & it works equally well too (using normal single dozen progression).
Warnings & improvement: Now the reason i chose to judge between the last 12 numbers is because my current online site shows the last 12 numbers, so it could as well be 10 or 14 or even 20 numbers that your site shows. I do think that 10-14 is a good range to judge from especially considering the "catchup" effect can happen near instantly .. aka if Black Dozen 1 has been cold it suddenly "catches up" while you are betting the other 2 dozens. A good rule would be to stop betting if your first 2 spins happens to be from the same one cold/sleeping group. Oh and for the same reason do make sure to revise your choice of both the hottest colour & group(s) after each win. Oh, and there is situations where you can argue for playing the hottest group from both colours, but i havnt tested this at all.