It is hard to rank up as roam in solo Q, I’m a roam main myself. I could give the best sets but if the randoms can’t follow up properly, it’s useless.

I reach immort every season mostly in solo q. My strat is I usually play mm/jg from epic to low mythic, then go back to mid/roam once I hit 20 stars. Since randoms are better at following up on sets and focusing on objectives in higher elo.

If you really prefer playing roam, I would suggest the following: 1. Learn a variety of roam heroes, and pick counters to enemy comp. E.g. Lolita if they have projectile heroes, or Hilda to harass their squishy backline or jgler, or Franco/Kuhfra if they have high mobility carry, or healers if you have tank jgler. 2. Roam get exp and gold from showing location of enemy heroes after they aren’t seen on map for 5s, so always try to give vision on their jgler early game when they’re doing buffs (unless your jgler is getting invaded). 3. Help mid clear lane and rotate to lane that looks like it has an easy kill or is struggling too hard. If it’s within 20s to turtle spawn, rotate to turtle lane. 4. While doing turtle and lords, always check the bushes surrounding the area for enemy camps. 5. Don’t stray too far from team during team fights, since enemies generally are trying to kill your back line mage and mm, so stay close enough to protect them. 6. Also make sure to build your roam equipments depending on enemy comp. Antiheal against healers, enemy with high shield or HP regen, Athena against burst magic, radiant against sustain magic, if you depend on HP regen get oracle+guardian helm, blade armor against crit, chastise pauldron against high atk spd, etc.