Don't play Bard myself but I have a friend who does, and these are some things that I see him do that should help you a little.
There is a super long portal you can make from the edge of the fountain towards bot lane that will save you some time when going back into lane, it covers about half of the base. Dificult to aim it right though.
When you get multiple meeps in lane, USE THEM. Don't sit back and do nothing for the next two minutes. They are great for harassing laners in short trades. Don't force trades just because you got meeps, but keep in mind that you should try to use it within a reasonable time limit. However, try to save one for safety reasons for when enemy jungle ganks. If you get the slow upgrade from chimes, then it adds a little additional protection to your adc and you.
When roaming for chimes (keeping in mind what 3sheetstothewind said about leaving lane while your adc is csing) try to gank a lane if you are nearby and the enemy is in a good position for it. This will help your whole team out from you roaming and it won't just be, "Welp, Bard left lane, its a 4v5 now." This will add additional map pressure and make enemy laners nervous whenever bot pings mia for you.
It can sometimes be a good idea to place a heal shrine to the side of the minion waves, not super close to river, but far enough that someone has to purposefully move to get to it. People go nuts to try and kill shrines when Bard is on the enemy team, and either the enemy support or adc will eventually try to go for it. This gets them out of position and out from behind minions, making it easier to start and win trades against them (especially if you have a skillshot oriented adc like
or
). And if they don't get it, your adc or jungler can just take it normally when the lane is pushed up so you lose nothing.
People are dumb about Bard portals when they are fighting against him. If an enemy takes a portal, wait for them on the other side and q right into their face just a split second before they come out. It will lead to an automatic stun since they are against a wall, and will lead to either killing them, chasing them off, or allowing you to run away and survive what would have been certain death otherwise.
If you catch 2 people in your ult, line up next to them and q them right as the ult fades off (you really need to learn the timing for this one.) Chain cc is one of the best thing you can do for your team if you are in a teamfight, just use the ult to position yourself well and screw them over again when its over.
Your ult is one of the best stalls in the game. It buys time for your entire team and has a ton of uses. It can cover towers that are about to be killed, catch an enemy out of position so your team can kill them mercilessly, save a teamate by letting allies get to them and protect them, objective control, and so on. However, it does nothing by itself. If you land an ult and you and your team don't use it to reposition to do something about what you ulted, it was wasted. Its all about positioning, don't ult it if you or your team aren't close enough to save it or kill it afterwards.
Bard is a super complex champ (imo) and there are a LOT more tips than this for using him, but since I don't know him super well this is all I could come up with off the top of my head. The best way to learn more is by just spamming him in games and learning what cool tricks you can and can't do with him. Hope this helped somewhat.